CWE - VIEW SLICE: CWE-660: Weaknesses in Software Written in Java (4.15)

CWE VIEW: Weaknesses in Software Written in Java

View ID: 660

Vulnerability Mapping: PROHIBITEDThis CWE ID must not be used to map to real-world vulnerabilities
Type: Implicit

Downloads: Booklet | CSV | XML

Objective

This view (slice) covers issues that are found in Java programs that are not common to all languages.

Filter

/Weakness_Catalog/Weaknesses/Weakness[./Applicable_Platforms/Language/@Name='Java']

Membership

Nature	Type	ID	Name
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	5	J2EE Misconfiguration: Data Transmission Without Encryption
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	6	J2EE Misconfiguration: Insufficient Session-ID Length
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	7	J2EE Misconfiguration: Missing Custom Error Page
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	95	Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	102	Struts: Duplicate Validation Forms
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	103	Struts: Incomplete validate() Method Definition
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	104	Struts: Form Bean Does Not Extend Validation Class
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	105	Struts: Form Field Without Validator
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	106	Struts: Plug-in Framework not in Use
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	107	Struts: Unused Validation Form
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	108	Struts: Unvalidated Action Form
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	109	Struts: Validator Turned Off
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	110	Struts: Validator Without Form Field
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	111	Direct Use of Unsafe JNI
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	191	Integer Underflow (Wrap or Wraparound)
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	192	Integer Coercion Error
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	197	Numeric Truncation Error
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	209	Generation of Error Message Containing Sensitive Information
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	245	J2EE Bad Practices: Direct Management of Connections
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	246	J2EE Bad Practices: Direct Use of Sockets
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	248	Uncaught Exception
HasMember	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	362	Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	366	Race Condition within a Thread
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	374	Passing Mutable Objects to an Untrusted Method
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	375	Returning a Mutable Object to an Untrusted Caller
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	382	J2EE Bad Practices: Use of System.exit()
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	383	J2EE Bad Practices: Direct Use of Threads
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	395	Use of NullPointerException Catch to Detect NULL Pointer Dereference
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	396	Declaration of Catch for Generic Exception
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	397	Declaration of Throws for Generic Exception
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	460	Improper Cleanup on Thrown Exception
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	462	Duplicate Key in Associative List (Alist)
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	470	Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	476	NULL Pointer Dereference
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	478	Missing Default Case in Multiple Condition Expression
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	481	Assigning instead of Comparing
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	484	Omitted Break Statement in Switch
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	486	Comparison of Classes by Name
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	487	Reliance on Package-level Scope
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	491	Public cloneable() Method Without Final ('Object Hijack')
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	492	Use of Inner Class Containing Sensitive Data
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	493	Critical Public Variable Without Final Modifier
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	495	Private Data Structure Returned From A Public Method
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	496	Public Data Assigned to Private Array-Typed Field
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	498	Cloneable Class Containing Sensitive Information
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	499	Serializable Class Containing Sensitive Data
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	500	Public Static Field Not Marked Final
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	502	Deserialization of Untrusted Data
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	537	Java Runtime Error Message Containing Sensitive Information
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	543	Use of Singleton Pattern Without Synchronization in a Multithreaded Context
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	567	Unsynchronized Access to Shared Data in a Multithreaded Context
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	568	finalize() Method Without super.finalize()
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	572	Call to Thread run() instead of start()
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	574	EJB Bad Practices: Use of Synchronization Primitives
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	575	EJB Bad Practices: Use of AWT Swing
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	576	EJB Bad Practices: Use of Java I/O
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	577	EJB Bad Practices: Use of Sockets
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	578	EJB Bad Practices: Use of Class Loader
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	579	J2EE Bad Practices: Non-serializable Object Stored in Session
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	580	clone() Method Without super.clone()
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	581	Object Model Violation: Just One of Equals and Hashcode Defined
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	582	Array Declared Public, Final, and Static
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	583	finalize() Method Declared Public
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	585	Empty Synchronized Block
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	586	Explicit Call to Finalize()
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	594	J2EE Framework: Saving Unserializable Objects to Disk
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	595	Comparison of Object References Instead of Object Contents
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	607	Public Static Final Field References Mutable Object
HasMember	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	608	Struts: Non-private Field in ActionForm Class
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	609	Double-Checked Locking
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	766	Critical Data Element Declared Public
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	767	Access to Critical Private Variable via Public Method
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	917	Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1235	Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1335	Incorrect Bitwise Shift of Integer
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1336	Improper Neutralization of Special Elements Used in a Template Engine
HasMember	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1341	Multiple Releases of Same Resource or Handle

Vulnerability Mapping Notes

Usage: PROHIBITED

(this CWE ID must not be used to map to real-world vulnerabilities)

Reason: View

Rationale:

This entry is a View. Views are not weaknesses and therefore inappropriate to describe the root causes of vulnerabilities.

Comments:

Use this View or other Views to search and navigate for the appropriate weakness.

View Metrics

	CWEs in this view		Total CWEs
Weaknesses	77	out of	939
Categories	0	out of	374
Views	0	out of	50
Total	77	out of	1363

Content History

Submissions
Submission Date	Submitter	Organization
2008-04-11 (CWE Draft 9, 2008-04-11)	CWE Content Team	MITRE
2008-04-11 (CWE Draft 9, 2008-04-11)
Modifications
Modification Date	Modifier	Organization
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Name, View_Filter, View_Structure
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-09-09	Weaknesses found in the Java Language

View Components

Weakness ID: 767

Vulnerability Mapping: ALLOWEDThis CWE ID may be used to map to real-world vulnerabilities
Abstraction: BaseBase - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.

View customized information:

For users who are interested in more notional aspects of a weakness. Example: educators, technical writers, and project/program managers. For users who are concerned with the practical application and details about the nature of a weakness and how to prevent it from happening. Example: tool developers, security researchers, pen-testers, incident response analysts. For users who are mapping an issue to CWE/CAPEC IDs, i.e., finding the most appropriate CWE for a specific issue (e.g., a CVE record). Example: tool developers, security researchers. For users who wish to see all available information for the CWE/CAPEC entry. For users who want to customize what details are displayed.

Description

The product defines a public method that reads or modifies a private variable.

Extended Description

If an attacker modifies the variable to contain unexpected values, this could violate assumptions from other parts of the code. Additionally, if an attacker can read the private variable, it may expose sensitive information or make it easier to launch further attacks.

Common Consequences

This table specifies different individual consequences associated with the weakness. The Scope identifies the application security area that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in exploiting this weakness. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a weakness will be exploited to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Modify Application Data; Other

Potential Mitigations

Phase: Implementation

Use class accessor and mutator methods appropriately. Perform validation when accepting data from a public method that is intended to modify a critical private variable. Also be sure that appropriate access controls are being applied when a public method interfaces with critical data.

Relationships

This table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	275	Permission Issues

Modes Of Introduction

The different Modes of Introduction provide information about how and when this weakness may be introduced. The Phase identifies a point in the life cycle at which introduction may occur, while the Note provides a typical scenario related to introduction during the given phase.

Phase	Note
Implementation

Applicable Platforms

This listing shows possible areas for which the given weakness could appear. These may be for specific named Languages, Operating Systems, Architectures, Paradigms, Technologies, or a class of such platforms. The platform is listed along with how frequently the given weakness appears for that instance.

Languages

C++ (Undetermined Prevalence)

C# (Undetermined Prevalence)

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following example declares a critical variable to be private, and then allows the variable to be modified by public methods.

(bad code)

Example Language: C++

private: float price;
public: void changePrice(float newPrice) {

price = newPrice;

}

Example 2

The following example could be used to implement a user forum where a single user (UID) can switch between multiple profiles (PID).

(bad code)

Example Language: Java

public class Client {

private int UID;
public int PID;
private String userName;
public Client(String userName){

PID = getDefaultProfileID();
UID = mapUserNametoUID( userName );
this.userName = userName;

}
public void setPID(int ID) {

UID = ID;

}

The programmer implemented setPID with the intention of modifying the PID variable, but due to a typo. accidentally specified the critical variable UID instead. If the program allows profile IDs to be between 1 and 10, but a UID of 1 means the user is treated as an admin, then a user could gain administrative privileges as a result of this typo.

Memberships

This MemberOf Relationships table shows additional CWE Categories and Views that reference this weakness as a member. This information is often useful in understanding where a weakness fits within the context of external information sources.

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1184	SEI CERT Perl Coding Standard - Guidelines 06. Object-Oriented Programming (OOP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Notes

Maintenance

This entry is closely associated with access control for public methods. If the public methods are restricted with proper access controls, then the information in the private variable will not be exposed to unexpected parties. There may be chaining or composite relationships between improper access controls and this weakness.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Failure to protect stored data from modification
Software Fault Patterns	SFP23		Exposed Data
SEI CERT Perl Coding Standard	OOP31-PL	Imprecise	Do not access private variables or subroutines in other packages

Content History

Submissions
Submission Date	Submitter	Organization
2009-03-03 (CWE 1.4, 2009-05-27)	CWE Content Team	MITRE
2009-03-03 (CWE 1.4, 2009-05-27)
Modifications
Modification Date	Modifier	Organization
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Likelihood_of_Exploit, Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction, Type
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 582

Vulnerability Mapping: ALLOWEDThis CWE ID may be used to map to real-world vulnerabilities
Abstraction: VariantVariant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.

View customized information:

Description

The product declares an array public, final, and static, which is not sufficient to prevent the array's contents from being modified.

Extended Description

Because arrays are mutable objects, the final constraint requires that the array object itself be assigned only once, but makes no guarantees about the values of the array elements. Since the array is public, a malicious program can change the values stored in the array. As such, in most cases an array declared public, final and static is a bug.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data

Potential Mitigations

Phase: Implementation

In most situations the array should be made private.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Background Details

Mobile code, in this case a Java Applet, is code that is transmitted across a network and executed on a remote machine. Because mobile code developers have little if any control of the environment in which their code will execute, special security concerns become relevant. One of the biggest environmental threats results from the risk that the mobile code will run side-by-side with other, potentially malicious, mobile code. Because all of the popular web browsers execute code from multiple sources together in the same JVM, many of the security guidelines for mobile code are focused on preventing manipulation of your objects' state and behavior by adversaries who have access to the same virtual machine where your product is running.

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java Applet code mistakenly declares an array public, final and static.

(bad code)

Example Language: Java

public final class urlTool extends Applet {

public final static URL[] urls;
...

}

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ10-J		Do not use public static nonfinal variables
Software Fault Patterns	SFP28		Unexpected Access Points

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Other_Notes, Weakness_Ordinalities
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Background_Details, Demonstrative_Examples, Description, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships, Taxonomy_Mappings
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Taxonomy_Mappings
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Background_Details, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Mobile Code: Unsafe Array Declaration

Weakness ID: 481

View customized information:

Description

The code uses an operator for assignment when the intention was to perform a comparison.

Extended Description

In many languages the compare statement is very close in appearance to the assignment statement and are often confused. This bug is generally the result of a typo and usually causes obvious problems with program execution. If the comparison is in an if statement, the if statement will usually evaluate the value of the right-hand side of the predicate.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Alter Execution Logic

Potential Mitigations

Phase: Testing

Many IDEs and static analysis products will detect this problem.

Phase: Implementation

Place constants on the left. If one attempts to assign a constant with a variable, the compiler will produce an error.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	480	Use of Incorrect Operator
CanPrecede	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	697	Incorrect Comparison

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Low

Demonstrative Examples

Example 1

The following C/C++ and C# examples attempt to validate an int input parameter against the integer value 100.

(bad code)

Example Language: C

int isValid(int value) {

if (value=100) {

printf("Value is valid\n");
return(1);

}
printf("Value is not valid\n");
return(0);

}

(bad code)

Example Language: C#

bool isValid(int value) {

if (value=100) {

Console.WriteLine("Value is valid.");
return true;

}
Console.WriteLine("Value is not valid.");
return false;

}

However, the expression to be evaluated in the if statement uses the assignment operator "=" rather than the comparison operator "==". The result of using the assignment operator instead of the comparison operator causes the int variable to be reassigned locally and the expression in the if statement will always evaluate to the value on the right hand side of the expression. This will result in the input value not being properly validated, which can cause unexpected results.

Example 2

In this example, we show how assigning instead of comparing can impact code when values are being passed by reference instead of by value. Consider a scenario in which a string is being processed from user input. Assume the string has already been formatted such that different user inputs are concatenated with the colon character. When the processString function is called, the test for the colon character will result in an insertion of the colon character instead, adding new input separators. Since the string was passed by reference, the data sentinels will be inserted in the original string (CWE-464), and further processing of the inputs will be altered, possibly malformed..

(bad code)

Example Language: C

void processString (char *str) {

int i;

for(i=0; i<strlen(str); i++) {

if (isalnum(str[i])){

processChar(str[i]);

}
else if (str[i] = ':') {

movingToNewInput();}

}

Example 3

The following Java example attempts to perform some processing based on the boolean value of the input parameter. However, the expression to be evaluated in the if statement uses the assignment operator "=" rather than the comparison operator "==". As with the previous examples, the variable will be reassigned locally and the expression in the if statement will evaluate to true and unintended processing may occur.

(bad code)

Example Language: Java

public void checkValid(boolean isValid) {

if (isValid = true) {

System.out.println("Performing processing");
doSomethingImportant();

}
else {

System.out.println("Not Valid, do not perform processing");
return;

}

While most Java compilers will catch the use of an assignment operator when a comparison operator is required, for boolean variables in Java the use of the assignment operator within an expression is allowed. If possible, try to avoid using comparison operators on boolean variables in java. Instead, let the values of the variables stand for themselves, as in the following code.

(good code)

Example Language: Java

public void checkValid(boolean isValid) {

if (isValid) {

System.out.println("Performing processing");
doSomethingImportant();

}
else {

System.out.println("Not Valid, do not perform processing");
return;

}

Alternatively, to test for false, just use the boolean NOT operator.

(good code)

Example Language: Java

public void checkValid(boolean isValid) {

if (!isValid) {

System.out.println("Not Valid, do not perform processing");
return;

}
System.out.println("Performing processing");
doSomethingImportant();

}

Example 4

The following example demonstrates the weakness.

(bad code)

Example Language: C

void called(int foo){

if (foo=1) printf("foo\n");

}
int main() {

called(2);
return 0;

}

Detection Methods

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1157	SEI CERT C Coding Standard - Guidelines 03. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Assigning instead of comparing
Software Fault Patterns	SFP1		Glitch in computation
CERT C Secure Coding	EXP45-C	CWE More Abstract	Do not perform assignments in selection statements

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 6, "Typos", Page 289. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Description, Relationships, Other_Notes, Taxonomy_Mappings
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-01-19	CWE Content Team	MITRE
2017-01-19	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples, Potential_Mitigations
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 572

View customized information:

Description

The product calls a thread's run() method instead of calling start(), which causes the code to run in the thread of the caller instead of the callee.

Extended Description

In most cases a direct call to a Thread object's run() method is a bug. The programmer intended to begin a new thread of control, but accidentally called run() instead of start(), so the run() method will execute in the caller's thread of control.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation; Varies by Context

Potential Mitigations

Phase: Implementation

Use the start() method instead of the run() method.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	821	Incorrect Synchronization

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following excerpt from a Java program mistakenly calls run() instead of start().

(bad code)

Example Language: Java

Thread thr = new Thread() {

public void run() {

...

}

};

thr.run();

Detection Methods

Automated Static Analysis

Effectiveness: High

Affected Resources

System Process

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	854	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 11 - Thread APIs (THI)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1144	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 10. Thread APIs (THI)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	THI00-J		Do not invoke Thread.run()
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Description, Other_Notes
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Call to Thread.run()

Weakness ID: 580

View customized information:

Description

The product contains a clone() method that does not call super.clone() to obtain the new object.

Extended Description

All implementations of clone() should obtain the new object by calling super.clone(). If a class does not follow this convention, a subclass's clone() method will return an object of the wrong type.

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Unexpected State; Quality Degradation

Potential Mitigations

Phase: Implementation

Call super.clone() within your clone() method, when obtaining a new object.

Phase: Implementation

In some cases, you can eliminate the clone method altogether and use copy constructors.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	664	Improper Control of a Resource Through its Lifetime

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	265	Privilege Issues

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following two classes demonstrate a bug introduced by not calling super.clone(). Because of the way Kibitzer implements clone(), FancyKibitzer's clone method will return an object of type Kibitzer instead of FancyKibitzer.

(bad code)

Example Language: Java

public class Kibitzer {

public Object clone() throws CloneNotSupportedException {

Object returnMe = new Kibitzer();
...

}

}

public class FancyKibitzer extends Kibitzer{

public Object clone() throws CloneNotSupportedException {

Object returnMe = super.clone();
...

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP28		Unexpected access points

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Description, Other_Notes, Potential_Mitigations
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Description
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Erroneous Clone Method

Weakness ID: 498

View customized information:

Description

The code contains a class with sensitive data, but the class is cloneable. The data can then be accessed by cloning the class.

Extended Description

Cloneable classes are effectively open classes, since data cannot be hidden in them. Classes that do not explicitly deny cloning can be cloned by any other class without running the constructor.

Common Consequences

Scope	Impact	Likelihood
Access Control	Technical Impact: Bypass Protection Mechanism A class that can be cloned can be produced without executing the constructor. This is dangerous since the constructor may perform security-related checks. By allowing the object to be cloned, those checks may be bypassed.

Potential Mitigations

Phase: Implementation

If you do make your classes clonable, ensure that your clone method is final and throw super.clone().

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere
CanPrecede	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	200	Exposure of Sensitive Information to an Unauthorized Actor

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following example demonstrates the weakness.

(bad code)

Example Language: Java

public class CloneClient {

public CloneClient() //throws
java.lang.CloneNotSupportedException {

Teacher t1 = new Teacher("guddu","22,nagar road");
//...
// Do some stuff to remove the teacher.
Teacher t2 = (Teacher)t1.clone();
System.out.println(t2.name);

}
public static void main(String args[]) {

new CloneClient();

}

}
class Teacher implements Cloneable {

public Object clone() {

try {

return super.clone();

}
catch (java.lang.CloneNotSupportedException e) {

throw new RuntimeException(e.toString());

}

}
public String name;
public String clas;
public Teacher(String name,String clas) {

this.name = name;
this.clas = clas;

}

Make classes uncloneable by defining a clone function like:

(good code)

Example Language: Java

public final void clone() throws java.lang.CloneNotSupportedException {

throw new java.lang.CloneNotSupportedException();

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Information leak through class cloning
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ07-J	Sensitive classes must not let themselves be copied
Software Fault Patterns	SFP23	Exposed Data

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Description, Relationships, Other_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Common_Consequences, Description, Other_Notes, Potential_Mitigations
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Name
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Potential_Mitigations, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2011-03-29	Information Leak through Class Cloning

Weakness ID: 486

View customized information:

Description

The product compares classes by name, which can cause it to use the wrong class when multiple classes can have the same name.

Extended Description

If the decision to trust the methods and data of an object is based on the name of a class, it is possible for malicious users to send objects of the same name as trusted classes and thereby gain the trust afforded to known classes and types.

Common Consequences

Scope	Impact	Likelihood
Integrity Confidentiality Availability	Technical Impact: Execute Unauthorized Code or Commands If a product relies solely on the name of an object to determine identity, it may execute the incorrect or unintended code.

Potential Mitigations

Phase: Implementation

Use class equivalency to determine type. Rather than use the class name to determine if an object is of a given type, use the getClass() method, and == operator.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1025	Comparison Using Wrong Factors
PeerOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	386	Symbolic Name not Mapping to Correct Object

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

In this example, the expression in the if statement compares the class of the inputClass object to a trusted class by comparing the class names.

(bad code)

Example Language: Java

if (inputClass.getClass().getName().equals("TrustedClassName")) {

// Do something assuming you trust inputClass

// ...

}

However, multiple classes can have the same name therefore comparing an object's class by name can allow untrusted classes of the same name as the trusted class to be use to execute unintended or incorrect code. To compare the class of an object to the intended class the getClass() method and the comparison operator "==" should be used to ensure the correct trusted class is used, as shown in the following example.

(good code)

Example Language: Java

if (inputClass.getClass() == TrustedClass.class) {

// Do something assuming you trust inputClass

// ...

}

Example 2

In this example, the Java class, TrustedClass, overrides the equals method of the parent class Object to determine equivalence of objects of the class. The overridden equals method first determines if the object, obj, is the same class as the TrustedClass object and then compares the object's fields to determine if the objects are equivalent.

(bad code)

Example Language: Java

public class TrustedClass {

...

@Override
public boolean equals(Object obj) {

boolean isEquals = false;

// first check to see if the object is of the same class
if (obj.getClass().getName().equals(this.getClass().getName())) {

// then compare object fields
...
if (...) {

isEquals = true;

}

}

return isEquals;

}

...

}

However, the equals method compares the class names of the object, obj, and the TrustedClass object to determine if they are the same class. As with the previous example using the name of the class to compare the class of objects can lead to the execution of unintended or incorrect code if the object passed to the equals method is of another class with the same name. To compare the class of an object to the intended class, the getClass() method and the comparison operator "==" should be used to ensure the correct trusted class is used, as shown in the following example.

(good code)

Example Language: Java

public boolean equals(Object obj) {

...

// first check to see if the object is of the same class
if (obj.getClass() == this.getClass()) {

...

}

...

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1397	Comprehensive Categorization: Comparison

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Comparing Classes by Name
CLASP		Comparing classes by name
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ09-J	Compare classes and not class names
Software Fault Patterns	SFP1	Glitch in computation

References

[REF-6] Katrina Tsipenyuk, Brian Chess and Gary McGraw. "Seven Pernicious Kingdoms: A Taxonomy of Software Security Errors". NIST Workshop on Software Security Assurance Tools Techniques and Metrics. NIST. 2005-11-07. <https://samate.nist.gov/SSATTM_Content/papers/Seven%20Pernicious%20Kingdoms%20-%20Taxonomy%20of%20Sw%20Security%20Errors%20-%20Tsipenyuk%20-%20Chess%20-%20McGraw.pdf>.

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Description, Relationships, Other_Notes, Relevant_Properties, Taxonomy_Mappings
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Other_Notes
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, Relevant_Properties
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Common_Consequences, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Comparing Classes by Name

Weakness ID: 595

View customized information:

Description

The product compares object references instead of the contents of the objects themselves, preventing it from detecting equivalent objects.

Extended Description

For example, in Java, comparing objects using == usually produces deceptive results, since the == operator compares object references rather than values; often, this means that using == for strings is actually comparing the strings' references, not their values.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Varies by Context This weakness can lead to erroneous results that can cause unexpected application behaviors.

Potential Mitigations

Phase: Implementation

In Java, use the equals() method to compare objects instead of the == operator. If using ==, it is important for performance reasons that your objects are created by a static factory, not by a constructor.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1025	Comparison Using Wrong Factors
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	597	Use of Wrong Operator in String Comparison

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	597	Use of Wrong Operator in String Comparison
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1097	Persistent Storable Data Element without Associated Comparison Control Element

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Class: Not Language-Specific (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the example below, two Java String objects are declared and initialized with the same string values. An if statement is used to determine if the strings are equivalent.

(bad code)

Example Language: Java

String str1 = new String("Hello");
String str2 = new String("Hello");
if (str1 == str2) {

System.out.println("str1 == str2");

}

However, the if statement will not be executed as the strings are compared using the "==" operator. For Java objects, such as String objects, the "==" operator compares object references, not object values. While the two String objects above contain the same string values, they refer to different object references, so the System.out.println statement will not be executed. To compare object values, the previous code could be modified to use the equals method:

(good code)

if (str1.equals(str2)) {

System.out.println("str1 equals str2");

}

Example 2

In the following Java example, two BankAccount objects are compared in the isSameAccount method using the == operator.

(bad code)

Example Language: Java

public boolean isSameAccount(BankAccount accountA, BankAccount accountB) {

return accountA == accountB;

}

Using the == operator to compare objects may produce incorrect or deceptive results by comparing object references rather than values. The equals() method should be used to ensure correct results or objects should contain a member variable that uniquely identifies the object.

The following example shows the use of the equals() method to compare the BankAccount objects and the next example uses a class get method to retrieve the bank account number that uniquely identifies the BankAccount object to compare the objects.

(good code)

Example Language: Java

public boolean isSameAccount(BankAccount accountA, BankAccount accountB) {

return accountA.equals(accountB);

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	847	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 4 - Expressions (EXP)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	977	SFP Secondary Cluster: Design
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1136	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 02. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1306	CISQ Quality Measures - Reliability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1397	Comprehensive Categorization: Comparison

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	EXP02-J	Use the two-argument Arrays.equals() method to compare the contents of arrays
The CERT Oracle Secure Coding Standard for Java (2011)	EXP02-J	Use the two-argument Arrays.equals() method to compare the contents of arrays
The CERT Oracle Secure Coding Standard for Java (2011)	EXP03-J	Do not use the equality operators when comparing values of boxed primitives

References

[REF-954] Mozilla MDN. "Equality comparisons and sameness". <https://developer.mozilla.org/en-US/docs/Web/JavaScript/Equality_comparisons_and_sameness>. URL validated: 2017-11-17.

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Content Team	MITRE
2006-12-15 (CWE Draft 5, 2006-12-15)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Name
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Demonstrative_Examples, Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Applicable_Platforms, Common_Consequences
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Applicable_Platforms, Common_Consequences, Description, Other_Notes, Potential_Mitigations, References, Relationships, Type
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Incorrect Object Comparison: Syntactic

2009-05-27	Incorrect Syntactic Object Comparison

Weakness ID: 362

Vulnerability Mapping: ALLOWEDThis CWE ID could be used to map to real-world vulnerabilities in limited situations requiring careful review (with careful review of mapping notes)
Abstraction: ClassClass - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.

View customized information:

Description

The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently.

Extended Description

This can have security implications when the expected synchronization is in security-critical code, such as recording whether a user is authenticated or modifying important state information that should not be influenced by an outsider.

A race condition occurs within concurrent environments, and is effectively a property of a code sequence. Depending on the context, a code sequence may be in the form of a function call, a small number of instructions, a series of program invocations, etc.

A race condition violates these properties, which are closely related:

Exclusivity - the code sequence is given exclusive access to the shared resource, i.e., no other code sequence can modify properties of the shared resource before the original sequence has completed execution.
Atomicity - the code sequence is behaviorally atomic, i.e., no other thread or process can concurrently execute the same sequence of instructions (or a subset) against the same resource.

A race condition exists when an "interfering code sequence" can still access the shared resource, violating exclusivity. Programmers may assume that certain code sequences execute too quickly to be affected by an interfering code sequence; when they are not, this violates atomicity. For example, the single "x++" statement may appear atomic at the code layer, but it is actually non-atomic at the instruction layer, since it involves a read (the original value of x), followed by a computation (x+1), followed by a write (save the result to x).

The interfering code sequence could be "trusted" or "untrusted." A trusted interfering code sequence occurs within the product; it cannot be modified by the attacker, and it can only be invoked indirectly. An untrusted interfering code sequence can be authored directly by the attacker, and typically it is external to the vulnerable product.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other) When a race condition makes it possible to bypass a resource cleanup routine or trigger multiple initialization routines, it may lead to resource exhaustion (CWE-400).
Availability	Technical Impact: DoS: Crash, Exit, or Restart; DoS: Instability When a race condition allows multiple control flows to access a resource simultaneously, it might lead the product(s) into unexpected states, possibly resulting in a crash.
Confidentiality Integrity	Technical Impact: Read Files or Directories; Read Application Data When a race condition is combined with predictable resource names and loose permissions, it may be possible for an attacker to overwrite or access confidential data (CWE-59).

Potential Mitigations

Phase: Architecture and Design

In languages that support it, use synchronization primitives. Only wrap these around critical code to minimize the impact on performance.

Phase: Architecture and Design

Use thread-safe capabilities such as the data access abstraction in Spring.

Phase: Architecture and Design

Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.

Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

Phase: Implementation

When using multithreading and operating on shared variables, only use thread-safe functions.

Phase: Implementation

Use atomic operations on shared variables. Be wary of innocent-looking constructs such as "x++". This may appear atomic at the code layer, but it is actually non-atomic at the instruction layer, since it involves a read, followed by a computation, followed by a write.

Phase: Implementation

Use a mutex if available, but be sure to avoid related weaknesses such as CWE-412.

Phase: Implementation

Avoid double-checked locking (CWE-609) and other implementation errors that arise when trying to avoid the overhead of synchronization.

Phase: Implementation

Disable interrupts or signals over critical parts of the code, but also make sure that the code does not go into a large or infinite loop.

Phase: Implementation

Use the volatile type modifier for critical variables to avoid unexpected compiler optimization or reordering. This does not necessarily solve the synchronization problem, but it can help.

Phases: Architecture and Design; Operation

Strategy: Environment Hardening

Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	691	Insufficient Control Flow Management
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	364	Signal Handler Race Condition
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	366	Race Condition within a Thread
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	367	Time-of-check Time-of-use (TOCTOU) Race Condition
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	368	Context Switching Race Condition
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	421	Race Condition During Access to Alternate Channel
ParentOf	Composite - a Compound Element that consists of two or more distinct weaknesses, in which all weaknesses must be present at the same time in order for a potential vulnerability to arise. Removing any of the weaknesses eliminates or sharply reduces the risk. One weakness, X, can be "broken down" into component weaknesses Y and Z. There can be cases in which one weakness might not be essential to a composite, but changes the nature of the composite when it becomes a vulnerability.	689	Permission Race Condition During Resource Copy
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1223	Race Condition for Write-Once Attributes
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1298	Hardware Logic Contains Race Conditions
CanFollow	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization
CanPrecede	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	416	Use After Free
CanPrecede	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	476	NULL Pointer Dereference

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1003	Weaknesses for Simplified Mapping of Published Vulnerabilities
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	367	Time-of-check Time-of-use (TOCTOU) Race Condition

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation

Applicable Platforms

Languages

C (Sometimes Prevalent)

C++ (Sometimes Prevalent)

Java (Sometimes Prevalent)

Technologies

Class: Mobile (Undetermined Prevalence)

Class: ICS/OT (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

This code could be used in an e-commerce application that supports transfers between accounts. It takes the total amount of the transfer, sends it to the new account, and deducts the amount from the original account.

(bad code)

Example Language: Perl

$transfer_amount = GetTransferAmount();
$balance = GetBalanceFromDatabase();

if ($transfer_amount < 0) {

FatalError("Bad Transfer Amount");

}
$newbalance = $balance - $transfer_amount;
if (($balance - $transfer_amount) < 0) {

FatalError("Insufficient Funds");

}
SendNewBalanceToDatabase($newbalance);
NotifyUser("Transfer of $transfer_amount succeeded.");
NotifyUser("New balance: $newbalance");

A race condition could occur between the calls to GetBalanceFromDatabase() and SendNewBalanceToDatabase().

Suppose the balance is initially 100.00. An attack could be constructed as follows:

(attack code)

Example Language: Other

In the following pseudocode, the attacker makes two simultaneous calls of the program, CALLER-1 and CALLER-2. Both callers are for the same user account.
CALLER-1 (the attacker) is associated with PROGRAM-1 (the instance that handles CALLER-1). CALLER-2 is associated with PROGRAM-2.
CALLER-1 makes a transfer request of 80.00.
PROGRAM-1 calls GetBalanceFromDatabase and sets $balance to 100.00
PROGRAM-1 calculates $newbalance as 20.00, then calls SendNewBalanceToDatabase().
Due to high server load, the PROGRAM-1 call to SendNewBalanceToDatabase() encounters a delay.
CALLER-2 makes a transfer request of 1.00.
PROGRAM-2 calls GetBalanceFromDatabase() and sets $balance to 100.00. This happens because the previous PROGRAM-1 request was not processed yet.
PROGRAM-2 determines the new balance as 99.00.
After the initial delay, PROGRAM-1 commits its balance to the database, setting it to 20.00.
PROGRAM-2 sends a request to update the database, setting the balance to 99.00

At this stage, the attacker should have a balance of 19.00 (due to 81.00 worth of transfers), but the balance is 99.00, as recorded in the database.

To prevent this weakness, the programmer has several options, including using a lock to prevent multiple simultaneous requests to the web application, or using a synchronization mechanism that includes all the code between GetBalanceFromDatabase() and SendNewBalanceToDatabase().

Example 2

The following function attempts to acquire a lock in order to perform operations on a shared resource.

(bad code)

Example Language: C

void f(pthread_mutex_t *mutex) {

pthread_mutex_lock(mutex);

/* access shared resource */

pthread_mutex_unlock(mutex);

}

However, the code does not check the value returned by pthread_mutex_lock() for errors. If pthread_mutex_lock() cannot acquire the mutex for any reason, the function may introduce a race condition into the program and result in undefined behavior.

In order to avoid data races, correctly written programs must check the result of thread synchronization functions and appropriately handle all errors, either by attempting to recover from them or reporting them to higher levels.

(good code)

Example Language: C

int f(pthread_mutex_t *mutex) {

int result;

result = pthread_mutex_lock(mutex);
if (0 != result)

return result;

/* access shared resource */

return pthread_mutex_unlock(mutex);

}

Example 3

Suppose a processor's Memory Management Unit (MMU) has 5 other shadow MMUs to distribute its workload for its various cores. Each MMU has the start address and end address of "accessible" memory. Any time this accessible range changes (as per the processor's boot status), the main MMU sends an update message to all the shadow MMUs.

Suppose the interconnect fabric does not prioritize such "update" packets over other general traffic packets. This introduces a race condition. If an attacker can flood the target with enough messages so that some of those attack packets reach the target before the new access ranges gets updated, then the attacker can leverage this scenario.

Observed Examples

Reference	Description
CVE-2022-29527	Go application for cloud management creates a world-writable sudoers file that allows local attackers to inject sudo rules and escalate privileges to root by winning a race condition.
CVE-2021-1782	Chain: improper locking (CWE-667) leads to race condition (CWE-362), as exploited in the wild per CISA KEV.
CVE-2021-0920	Chain: mobile platform race condition (CWE-362) leading to use-after-free (CWE-416), as exploited in the wild per CISA KEV.
CVE-2020-6819	Chain: race condition (CWE-362) leads to use-after-free (CWE-416), as exploited in the wild per CISA KEV.
CVE-2019-18827	chain: JTAG interface is not disabled (CWE-1191) during ROM code execution, introducing a race condition (CWE-362) to extract encryption keys
CVE-2019-1161	Chain: race condition (CWE-362) in anti-malware product allows deletion of files by creating a junction (CWE-1386) and using hard links during the time window in which a temporary file is created and deleted.
CVE-2015-1743	TOCTOU in sandbox process allows installation of untrusted browser add-ons by replacing a file after it has been verified, but before it is executed
CVE-2014-8273	Chain: chipset has a race condition (CWE-362) between when an interrupt handler detects an attempt to write-enable the BIOS (in violation of the lock bit), and when the handler resets the write-enable bit back to 0, allowing attackers to issue BIOS writes during the timing window [REF-1237].
CVE-2008-5044	Race condition leading to a crash by calling a hook removal procedure while other activities are occurring at the same time.
CVE-2008-2958	chain: time-of-check time-of-use (TOCTOU) race condition in program allows bypass of protection mechanism that was designed to prevent symlink attacks.
CVE-2008-1570	chain: time-of-check time-of-use (TOCTOU) race condition in program allows bypass of protection mechanism that was designed to prevent symlink attacks.
CVE-2008-0058	Unsynchronized caching operation enables a race condition that causes messages to be sent to a deallocated object.
CVE-2008-0379	Race condition during initialization triggers a buffer overflow.
CVE-2007-6599	Daemon crash by quickly performing operations and undoing them, which eventually leads to an operation that does not acquire a lock.
CVE-2007-6180	chain: race condition triggers NULL pointer dereference
CVE-2007-5794	Race condition in library function could cause data to be sent to the wrong process.
CVE-2007-3970	Race condition in file parser leads to heap corruption.
CVE-2008-5021	chain: race condition allows attacker to access an object while it is still being initialized, causing software to access uninitialized memory.
CVE-2009-4895	chain: race condition for an argument value, possibly resulting in NULL dereference
CVE-2009-3547	chain: race condition might allow resource to be released before operating on it, leading to NULL dereference
CVE-2006-5051	Chain: Signal handler contains too much functionality (CWE-828), introducing a race condition (CWE-362) that leads to a double free (CWE-415).

Detection Methods

Black Box

Black box methods may be able to identify evidence of race conditions via methods such as multiple simultaneous connections, which may cause the software to become instable or crash. However, race conditions with very narrow timing windows would not be detectable.

White Box

Common idioms are detectable in white box analysis, such as time-of-check-time-of-use (TOCTOU) file operations (CWE-367), or double-checked locking (CWE-609).

Automated Dynamic Analysis

This weakness can be detected using dynamic tools and techniques that interact with the software using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The software's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

Race conditions may be detected with a stress-test by calling the software simultaneously from a large number of threads or processes, and look for evidence of any unexpected behavior.

Insert breakpoints or delays in between relevant code statements to artificially expand the race window so that it will be easier to detect.

Effectiveness: Moderate

Automated Static Analysis - Binary or Bytecode

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Bytecode Weakness Analysis - including disassembler + source code weakness analysis

Cost effective for partial coverage:

Binary Weakness Analysis - including disassembler + source code weakness analysis

Effectiveness: High

Dynamic Analysis with Automated Results Interpretation

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:

Web Application Scanner

Web Services Scanner

Database Scanners

Effectiveness: SOAR Partial

Dynamic Analysis with Manual Results Interpretation

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Framework-based Fuzzer

Cost effective for partial coverage:

Fuzz Tester

Monitored Virtual Environment - run potentially malicious code in sandbox / wrapper / virtual machine, see if it does anything suspicious

Effectiveness: High

Manual Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Manual Source Code Review (not inspections)

Cost effective for partial coverage:

Focused Manual Spotcheck - Focused manual analysis of source

Effectiveness: High

Automated Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Source code Weakness Analyzer

Context-configured Source Code Weakness Analyzer

Effectiveness: High

Architecture or Design Review

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Formal Methods / Correct-By-Construction

Cost effective for partial coverage:

Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	635	Weaknesses Originally Used by NVD from 2008 to 2016
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	743	CERT C Secure Coding Standard (2008) Chapter 10 - Input Output (FIO)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	751	2009 Top 25 - Insecure Interaction Between Components
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	801	2010 Top 25 - Insecure Interaction Between Components
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	852	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 9 - Visibility and Atomicity (VNA)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	867	2011 Top 25 - Weaknesses On the Cusp
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	877	CERT C++ Secure Coding Section 09 - Input Output (FIO)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	882	CERT C++ Secure Coding Section 14 - Concurrency (CON)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	988	SFP Secondary Cluster: Race Condition Window
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1142	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 08. Visibility and Atomicity (VNA)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1364	ICS Communications: Zone Boundary Failures
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1365	ICS Communications: Unreliability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1366	ICS Communications: Frail Security in Protocols
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1376	ICS Engineering (Construction/Deployment): Security Gaps in Commissioning
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1387	Weaknesses in the 2022 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1425	Weaknesses in the 2023 CWE Top 25 Most Dangerous Software Weaknesses

Vulnerability Mapping Notes

Usage: ALLOWED-WITH-REVIEW

(this CWE ID could be used to map to real-world vulnerabilities in limited situations requiring careful review)

Reason: Abstraction

Rationale:

This CWE entry is a Class and might have Base-level children that would be more appropriate

Comments:

Examine children of this entry to see if there is a better fit

Notes

Research Gap

Race conditions in web applications are under-studied and probably under-reported. However, in 2008 there has been growing interest in this area.

Research Gap

Much of the focus of race condition research has been in Time-of-check Time-of-use (TOCTOU) variants (CWE-367), but many race conditions are related to synchronization problems that do not necessarily require a time-of-check.

Research Gap

From a classification/taxonomy perspective, the relationships between concurrency and program state need closer investigation and may be useful in organizing related issues.

Maintenance

The relationship between race conditions and synchronization problems (CWE-662) needs to be further developed. They are not necessarily two perspectives of the same core concept, since synchronization is only one technique for avoiding race conditions, and synchronization can be used for other purposes besides race condition prevention.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Race Conditions
The CERT Oracle Secure Coding Standard for Java (2011)	VNA03-J		Do not assume that a group of calls to independently atomic methods is atomic

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-26	Leveraging Race Conditions
CAPEC-29	Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions

References

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 13: Race Conditions." Page 205. McGraw-Hill. 2010.

[REF-349] Andrei Alexandrescu. "volatile - Multithreaded Programmer's Best Friend". Dr. Dobb's. 2008-02-01. <https://drdobbs.com/cpp/volatile-the-multithreaded-programmers-b/184403766>. URL validated: 2023-04-07.

[REF-350] Steven Devijver. "Thread-safe webapps using Spring". <https://web.archive.org/web/20170609174845/http://www.javalobby.org/articles/thread-safe/index.jsp>. URL validated: 2023-04-07.

[REF-351] David Wheeler. "Prevent race conditions". 2007-10-04. <https://www.ida.liu.se/~TDDC90/literature/papers/SP-race-conditions.pdf>. URL validated: 2023-04-07.

[REF-352] Matt Bishop. "Race Conditions, Files, and Security Flaws; or the Tortoise and the Hare Redux". 1995-09. <https://seclab.cs.ucdavis.edu/projects/vulnerabilities/scriv/ucd-ecs-95-08.pdf>. URL validated: 2023-04-07.

[REF-353] David Wheeler. "Secure Programming for Linux and Unix HOWTO". 2003-03-03. <https://dwheeler.com/secure-programs/Secure-Programs-HOWTO/avoid-race.html>. URL validated: 2023-04-07.

[REF-354] Blake Watts. "Discovering and Exploiting Named Pipe Security Flaws for Fun and Profit". 2002-04. <https://www.blakewatts.com/blog/discovering-and-exploiting-named-pipe-security-flaws-for-fun-and-profit>. URL validated: 2023-04-07.

[REF-355] Roberto Paleari, Davide Marrone, Danilo Bruschi and Mattia Monga. "On Race Vulnerabilities in Web Applications". <http://security.dico.unimi.it/~roberto/pubs/dimva08-web.pdf>.

[REF-356] "Avoiding Race Conditions and Insecure File Operations". Apple Developer Connection. <https://web.archive.org/web/20081010155022/http://developer.apple.com/documentation/Security/Conceptual/SecureCodingGuide/Articles/RaceConditions.html>. URL validated: 2023-04-07.

[REF-357] Johannes Ullrich. "Top 25 Series - Rank 25 - Race Conditions". SANS Software Security Institute. 2010-03-26. <https://web.archive.org/web/20100530231203/http://blogs.sans.org:80/appsecstreetfighter/2010/03/26/top-25-series-rank-25-race-conditions/>. URL validated: 2023-04-07.

[REF-76] Sean Barnum and Michael Gegick. "Least Privilege". 2005-09-14. <https://web.archive.org/web/20211209014121/https://www.cisa.gov/uscert/bsi/articles/knowledge/principles/least-privilege>. URL validated: 2023-04-07.

[REF-1237] CERT Coordination Center. "Intel BIOS locking mechanism contains race condition that enables write protection bypass". 2015-01-05. <https://www.kb.cert.org/vuls/id/766164/>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	PLOVER
2006-07-19 (CWE Draft 3, 2006-07-19)
Contributions
Contribution Date	Contributor	Organization
2010-04-30	Martin Sebor	Cisco Systems, Inc.
2010-04-30	Provided Demonstrative Example
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Relationships
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Description, Likelihood_of_Exploit, Maintenance_Notes, Observed_Examples, Potential_Mitigations, References, Relationships, Research_Gaps
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Demonstrative_Examples, Potential_Mitigations
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Relationships
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Detection_Factors, References, Relationships
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Common_Consequences, Demonstrative_Examples, Detection_Factors, Potential_Mitigations, References
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Observed_Examples, Potential_Mitigations, Relationships
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Applicable_Platforms, Demonstrative_Examples, Description, Name, Potential_Mitigations, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Relationships
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Potential_Mitigations, References, Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Detection_Factors, Relationships
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, References, Research_Gaps, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Applicable_Platforms, Demonstrative_Examples, Observed_Examples, Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Observed_Examples, References
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Observed_Examples, Relationships
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Observed_Examples, Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Observed_Examples, References
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Applicable_Platforms, Common_Consequences, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes, Relationships
2024-07-16 (CWE 4.15, 2024-07-16)	CWE Content Team	MITRE
2024-07-16 (CWE 4.15, 2024-07-16)	updated Relationships
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Race Conditions

2010-12-13	Race Condition

Weakness ID: 766

View customized information:

Description

The product declares a critical variable, field, or member to be public when intended security policy requires it to be private.

Extended Description

This issue makes it more difficult to maintain the product, which indirectly affects security by making it more difficult or time-consuming to find and/or fix vulnerabilities. It also might make it easier to introduce vulnerabilities.

Common Consequences

Scope	Impact	Likelihood
Integrity Confidentiality	Technical Impact: Read Application Data; Modify Application Data Making a critical variable public allows anyone with access to the object in which the variable is contained to alter or read the value.
Other	Technical Impact: Reduce Maintainability

Potential Mitigations

Phase: Implementation

Data should be private, static, and final whenever possible. This will assure that your code is protected by instantiating early, preventing access, and preventing tampering.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1061	Insufficient Encapsulation
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	732	Incorrect Permission Assignment for Critical Resource

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	275	Permission Issues

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

C# (Undetermined Prevalence)

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following example declares a critical variable public, making it accessible to anyone with access to the object in which it is contained.

(bad code)

Example Language: C++

public: char* password;

Instead, the critical data should be declared private.

(good code)

Example Language: C++

private: char* password;

Even though this example declares the password to be private, there are other possible issues with this implementation, such as the possibility of recovering the password from process memory (CWE-257).

Example 2

The following example shows a basic user account class that includes member variables for the username and password as well as a public constructor for the class and a public method to authorize access to the user account.

(bad code)

Example Language: C++

#define MAX_PASSWORD_LENGTH 15
#define MAX_USERNAME_LENGTH 15

class UserAccount
{

public:

UserAccount(char *username, char *password)
{

if ((strlen(username) > MAX_USERNAME_LENGTH) ||
(strlen(password) > MAX_PASSWORD_LENGTH)) {

ExitError("Invalid username or password");

}
strcpy(this->username, username);
strcpy(this->password, password);

}

int authorizeAccess(char *username, char *password)
{

if ((strlen(username) > MAX_USERNAME_LENGTH) ||
(strlen(password) > MAX_PASSWORD_LENGTH)) {

ExitError("Invalid username or password");

}
// if the username and password in the input parameters are equal to

// the username and password of this account class then authorize access
if (strcmp(this->username, username) ||
strcmp(this->password, password))

return 0;

// otherwise do not authorize access
else

return 1;

}

char username[MAX_USERNAME_LENGTH+1];
char password[MAX_PASSWORD_LENGTH+1];

};

However, the member variables username and password are declared public and therefore will allow access and changes to the member variables to anyone with access to the object. These member variables should be declared private as shown below to prevent unauthorized access and changes.

(good code)

Example Language: C++

class UserAccount
{
public:

...

private:

char username[MAX_USERNAME_LENGTH+1];
char password[MAX_PASSWORD_LENGTH+1];

};

Observed Examples

Reference	Description
CVE-2010-3860	variables declared public allow remote read of system properties such as user name and home directory.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)
Indirect	(where the weakness is a quality issue that might indirectly make it easier to introduce security-relevant weaknesses or make them more difficult to detect)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1130	CISQ Quality Measures (2016) - Maintainability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Failure to protect stored data from modification
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ01-J	Declare data members as private and provide accessible wrapper methods
Software Fault Patterns	SFP28	Unexpected access points
OMG ASCMM	ASCMM-MNT-15

References

[REF-960] Object Management Group (OMG). "Automated Source Code Maintainability Measure (ASCMM)". ASCMM-MNT-15. 2016-01. <https://www.omg.org/spec/ASCMM/>. URL validated: 2023-04-07.

Content History

Submissions
Submission Date	Submitter	Organization
2009-03-03 (CWE 1.4, 2009-05-27)	CWE Content Team	MITRE
2009-03-03 (CWE 1.4, 2009-05-27)
Modifications
Modification Date	Modifier	Organization
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Observed_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Likelihood_of_Exploit, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Common_Consequences, Description, Name, References, Relationships, Taxonomy_Mappings, Weakness_Ordinalities
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, References, Relationships, Time_of_Introduction, Type
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes, Relationships
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2019-01-03	Critical Variable Declared Public

Weakness ID: 493

View customized information:

Description

The product has a critical public variable that is not final, which allows the variable to be modified to contain unexpected values.

Extended Description

If a field is non-final and public, it can be changed once the value is set by any function that has access to the class which contains the field. This could lead to a vulnerability if other parts of the program make assumptions about the contents of that field.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data The object could potentially be tampered with.
Confidentiality	Technical Impact: Read Application Data The object could potentially allow the object to be read.

Potential Mitigations

Phase: Implementation

Declare all public fields as final when possible, especially if it is used to maintain internal state of an Applet or of classes used by an Applet. If a field must be public, then perform all appropriate sanity checks before accessing the field from your code.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	500	Public Static Field Not Marked Final

Background Details

Mobile code, such as a Java Applet, is code that is transmitted across a network and executed on a remote machine. Because mobile code developers have little if any control of the environment in which their code will execute, special security concerns become relevant. One of the biggest environmental threats results from the risk that the mobile code will run side-by-side with other, potentially malicious, mobile code. Because all of the popular web browsers execute code from multiple sources together in the same JVM, many of the security guidelines for mobile code are focused on preventing manipulation of your objects' state and behavior by adversaries who have access to the same virtual machine where your program is running. Final provides security by only allowing non-mutable objects to be changed after being set. However, only objects which are not extended can be made final.

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

Suppose this WidgetData class is used for an e-commerce web site. The programmer attempts to prevent price-tampering attacks by setting the price of the widget using the constructor.

(bad code)

Example Language: Java

public final class WidgetData extends Applet {

public float price;
...
public WidgetData(...) {

this.price = LookupPrice("MyWidgetType");

}

The price field is not final. Even though the value is set by the constructor, it could be modified by anybody that has access to an instance of WidgetData.

Example 2

Assume the following code is intended to provide the location of a configuration file that controls execution of the application.

(bad code)

Example Language: C++

public string configPath = "/etc/application/config.dat";

(bad code)

Example Language: Java

public String configPath = new String("/etc/application/config.dat");

While this field is readable from any function, and thus might allow an information leak of a pathname, a more serious problem is that it can be changed by any function.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Mobile Code: Non-Final Public Field
CLASP		Failure to provide confidentiality for stored data
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ10-J	Do not use public static nonfinal variables
Software Fault Patterns	SFP28	Unexpected access points

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Description, Likelihood_of_Exploit, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Background_Details, Demonstrative_Examples, Description, Other_Notes, Potential_Mitigations
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Background_Details, Demonstrative_Examples, Description, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Mobile Code: Non-final Public Field

Weakness ID: 396

View customized information:

Description

Catching overly broad exceptions promotes complex error handling code that is more likely to contain security vulnerabilities.

Extended Description

Multiple catch blocks can get ugly and repetitive, but "condensing" catch blocks by catching a high-level class like Exception can obscure exceptions that deserve special treatment or that should not be caught at this point in the program. Catching an overly broad exception essentially defeats the purpose of a language's typed exceptions, and can become particularly dangerous if the program grows and begins to throw new types of exceptions. The new exception types will not receive any attention.

Common Consequences

Scope	Impact	Likelihood
Non-Repudiation Other	Technical Impact: Hide Activities; Alter Execution Logic

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	221	Information Loss or Omission
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	755	Improper Handling of Exceptional Conditions
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	705	Incorrect Control Flow Scoping

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	389	Error Conditions, Return Values, Status Codes

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Python (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code excerpt handles three types of exceptions in an identical fashion.

(good code)

Example Language: Java

try {

doExchange();

}
catch (IOException e) {

logger.error("doExchange failed", e);

}
catch (InvocationTargetException e) {

logger.error("doExchange failed", e);

}
catch (SQLException e) {

logger.error("doExchange failed", e);

}

At first blush, it may seem preferable to deal with these exceptions in a single catch block, as follows:

(bad code)

try {

doExchange();

}
catch (Exception e) {

logger.error("doExchange failed", e);

}

However, if doExchange() is modified to throw a new type of exception that should be handled in some different kind of way, the broad catch block will prevent the compiler from pointing out the situation. Further, the new catch block will now also handle exceptions derived from RuntimeException such as ClassCastException, and NullPointerException, which is not the programmer's intent.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	388	7PK - Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	960	SFP Secondary Cluster: Ambiguous Exception Type
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1129	CISQ Quality Measures (2016) - Reliability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1131	CISQ Quality Measures (2016) - Security
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Overly-Broad Catch Block
Software Fault Patterns	SFP5	Ambiguous Exception Type
OMG ASCSM	ASCSM-CWE-396
OMG ASCRM	ASCRM-CWE-396

References

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 9: Catching Exceptions." Page 157. McGraw-Hill. 2010.

[REF-961] Object Management Group (OMG). "Automated Source Code Reliability Measure (ASCRM)". ASCRM-CWE-396. 2016-01. <http://www.omg.org/spec/ASCRM/1.0/>.

[REF-962] Object Management Group (OMG). "Automated Source Code Security Measure (ASCSM)". ASCSM-CWE-396. 2016-01. <http://www.omg.org/spec/ASCSM/1.0/>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Contributions
Contribution Date	Contributor	Organization
2023-03-06	Drew Buttner	MITRE
2023-03-06	Suggested additional Applicable_Platforms and modification to extended description.
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Other_Notes, Taxonomy_Mappings
2008-09-24	CWE Content Team	MITRE
2008-09-24	Removed C from Applicable_Platforms
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Applicable_Platforms
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated References, Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Applicable_Platforms, Description, Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Overly-Broad Catch Block

Weakness ID: 397

View customized information:

Description

Throwing overly broad exceptions promotes complex error handling code that is more likely to contain security vulnerabilities.

Extended Description

Declaring a method to throw Exception or Throwable makes it difficult for callers to perform proper error handling and error recovery. Java's exception mechanism, for example, is set up to make it easy for callers to anticipate what can go wrong and write code to handle each specific exceptional circumstance. Declaring that a method throws a generic form of exception defeats this system.

Common Consequences

Scope	Impact	Likelihood
Non-Repudiation Other	Technical Impact: Hide Activities; Alter Execution Logic

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	221	Information Loss or Omission
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	703	Improper Check or Handling of Exceptional Conditions
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	705	Incorrect Control Flow Scoping

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	389	Error Conditions, Return Values, Status Codes

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following method throws three types of exceptions.

(good code)

Example Language: Java

public void doExchange() throws IOException, InvocationTargetException, SQLException {

...

}

While it might seem tidier to write

(bad code)

public void doExchange() throws Exception {

...

}

doing so hampers the caller's ability to understand and handle the exceptions that occur. Further, if a later revision of doExchange() introduces a new type of exception that should be treated differently than previous exceptions, there is no easy way to enforce this requirement.

Example 2

Early versions of C++ (C++98, C++03, C++11) included a feature known as Dynamic Exception Specification. This allowed functions to declare what type of exceptions it may throw. It is possible to declare a general class of exception to cover any derived exceptions that may be throw.

(bad code)

int myfunction() throw(std::exception) {

if (0) throw out_of_range();
throw length_error();

}

In the example above, the code declares that myfunction() can throw an exception of type "std::exception" thus hiding details about the possible derived exceptions that could potentially be thrown.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	388	7PK - Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	960	SFP Secondary Cluster: Ambiguous Exception Type
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1129	CISQ Quality Measures (2016) - Reliability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1131	CISQ Quality Measures (2016) - Security
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1141	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 07. Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Applicable Platform

For C++, this weakness only applies to C++98, C++03, and C++11. It relies on a feature known as Dynamic Exception Specification, which was part of early versions of C++ but was deprecated in C++11. It has been removed for C++17 and later.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Overly-Broad Throws Declaration
The CERT Oracle Secure Coding Standard for Java (2011)	ERR07-J	Do not throw RuntimeException, Exception, or Throwable
Software Fault Patterns	SFP5	Ambiguous Exception Type
OMG ASCSM	ASCSM-CWE-397
OMG ASCRM	ASCRM-CWE-397

References

[REF-961] Object Management Group (OMG). "Automated Source Code Reliability Measure (ASCRM)". ASCRM-CWE-397. 2016-01. <http://www.omg.org/spec/ASCRM/1.0/>.

[REF-962] Object Management Group (OMG). "Automated Source Code Security Measure (ASCSM)". ASCSM-CWE-397. 2016-01. <http://www.omg.org/spec/ASCSM/1.0/>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Other_Notes, Taxonomy_Mappings
2008-09-24	CWE Content Team	MITRE
2008-09-24	Removed C from Applicable_Platforms
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Applicable_Platforms
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Applicable_Platforms, Demonstrative_Examples, References, Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Overly-Broad Throws Declaration

Weakness ID: 502

View customized information:

Description

The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.

Extended Description

It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security -- which is a dangerous security assumption.

Data that is untrusted can not be trusted to be well-formed.

When developers place no restrictions on "gadget chains," or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.

Alternate Terms

Marshaling, Unmarshaling:	Marshaling and unmarshaling are effectively synonyms for serialization and deserialization, respectively.
Pickling, Unpickling:	In Python, the "pickle" functionality is used to perform serialization and deserialization.
PHP Object Injection:	Some PHP application researchers use this term when attacking unsafe use of the unserialize() function; but it is also used for CWE-915.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data; Unexpected State Attackers can modify unexpected objects or data that was assumed to be safe from modification.
Availability	Technical Impact: DoS: Resource Consumption (CPU) If a function is making an assumption on when to terminate, based on a sentry in a string, it could easily never terminate.
Other	Technical Impact: Varies by Context The consequences can vary widely, because it depends on which objects or methods are being deserialized, and how they are used. Making an assumption that the code in the deserialized object is valid is dangerous and can enable exploitation.

Potential Mitigations

Phases: Architecture and Design; Implementation

If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.

Phase: Implementation

When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.

Phase: Implementation

Explicitly define a final object() to prevent deserialization.

Phases: Architecture and Design; Implementation

Make fields transient to protect them from deserialization.

An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

Phase: Implementation

Avoid having unnecessary types or gadgets available that can be leveraged for malicious ends. This limits the potential for unintended or unauthorized types and gadgets to be leveraged by the attacker. Add only acceptable classes to an allowlist. Note: new gadgets are constantly being discovered, so this alone is not a sufficient mitigation.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	913	Improper Control of Dynamically-Managed Code Resources
PeerOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	915	Improperly Controlled Modification of Dynamically-Determined Object Attributes

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	399	Resource Management Errors

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	913	Improper Control of Dynamically-Managed Code Resources

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1019	Validate Inputs

Background Details

Serialization and deserialization refer to the process of taking program-internal object-related data, packaging it in a way that allows the data to be externally stored or transferred ("serialization"), then extracting the serialized data to reconstruct the original object ("deserialization").

Modes Of Introduction

Phase	Note
Architecture and Design	OMISSION: This weakness is caused by missing a security tactic during the architecture and design phase.
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Ruby (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Python (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

Technologies

Class: ICS/OT (Often Prevalent)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

This code snippet deserializes an object from a file and uses it as a UI button:

(bad code)

Example Language: Java

try {

File file = new File("object.obj");
ObjectInputStream in = new ObjectInputStream(new FileInputStream(file));
javax.swing.JButton button = (javax.swing.JButton) in.readObject();
in.close();

}

This code does not attempt to verify the source or contents of the file before deserializing it. An attacker may be able to replace the intended file with a file that contains arbitrary malicious code which will be executed when the button is pressed.

To mitigate this, explicitly define final readObject() to prevent deserialization. An example of this is:

(good code)

Example Language: Java

private final void readObject(ObjectInputStream in) throws java.io.IOException {
throw new java.io.IOException("Cannot be deserialized"); }

Example 2

In Python, the Pickle library handles the serialization and deserialization processes. In this example derived from [REF-467], the code receives and parses data, and afterwards tries to authenticate a user based on validating a token.

(bad code)

Example Language: Python

try {

class ExampleProtocol(protocol.Protocol):
def dataReceived(self, data):

# Code that would be here would parse the incoming data
# After receiving headers, call confirmAuth() to authenticate

def confirmAuth(self, headers):
try:
token = cPickle.loads(base64.b64decode(headers['AuthToken']))
if not check_hmac(token['signature'], token['data'], getSecretKey()):
raise AuthFail
self.secure_data = token['data']
except:
raise AuthFail

}

Unfortunately, the code does not verify that the incoming data is legitimate. An attacker can construct a illegitimate, serialized object "AuthToken" that instantiates one of Python's subprocesses to execute arbitrary commands. For instance,the attacker could construct a pickle that leverages Python's subprocess module, which spawns new processes and includes a number of arguments for various uses. Since Pickle allows objects to define the process for how they should be unpickled, the attacker can direct the unpickle process to call Popen in the subprocess module and execute /bin/sh.

Observed Examples

Reference	Description
CVE-2019-12799	chain: bypass of untrusted deserialization issue (CWE-502) by using an assumed-trusted class (CWE-183)
CVE-2015-8103	Deserialization issue in commonly-used Java library allows remote execution.
CVE-2015-4852	Deserialization issue in commonly-used Java library allows remote execution.
CVE-2013-1465	Use of PHP unserialize function on untrusted input allows attacker to modify application configuration.
CVE-2012-3527	Use of PHP unserialize function on untrusted input in content management system might allow code execution.
CVE-2012-0911	Use of PHP unserialize function on untrusted input in content management system allows code execution using a crafted cookie value.
CVE-2012-0911	Content management system written in PHP allows unserialize of arbitrary objects, possibly allowing code execution.
CVE-2011-2520	Python script allows local users to execute code via pickled data.
CVE-2012-4406	Unsafe deserialization using pickle in a Python script.
CVE-2003-0791	Web browser allows execution of native methods via a crafted string to a JavaScript function that deserializes the string.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	858	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 15 - Serialization (SER)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	994	SFP Secondary Cluster: Tainted Input to Variable
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1034	OWASP Top Ten 2017 Category A8 - Insecure Deserialization
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1148	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 14. Serialization (SER)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1200	Weaknesses in the 2019 CWE Top 25 Most Dangerous Software Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1308	CISQ Quality Measures - Security
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1337	Weaknesses in the 2021 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1340	CISQ Data Protection Measures
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1350	Weaknesses in the 2020 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1354	OWASP Top Ten 2021 Category A08:2021 - Software and Data Integrity Failures
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1387	Weaknesses in the 2022 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1415	Comprehensive Categorization: Resource Control
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1425	Weaknesses in the 2023 CWE Top 25 Most Dangerous Software Weaknesses

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Maintenance

The relationships between CWE-502 and CWE-915 need further exploration. CWE-915 is more narrowly scoped to object modification, and is not necessarily used for deserialization.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Deserialization of untrusted data
The CERT Oracle Secure Coding Standard for Java (2011)	SER01-J	Do not deviate from the proper signatures of serialization methods
The CERT Oracle Secure Coding Standard for Java (2011)	SER03-J	Do not serialize unencrypted, sensitive data
The CERT Oracle Secure Coding Standard for Java (2011)	SER06-J	Make defensive copies of private mutable components during deserialization
The CERT Oracle Secure Coding Standard for Java (2011)	SER08-J	Do not use the default serialized form for implementation defined invariants
Software Fault Patterns	SFP25	Tainted input to variable

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-586	Object Injection

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-461] Matthias Kaiser. "Exploiting Deserialization Vulnerabilities in Java". 2015-10-28. <https://www.slideshare.net/codewhitesec/exploiting-deserialization-vulnerabilities-in-java-54707478>. URL validated: 2023-04-07.

[REF-462] Sam Thomas. "PHP unserialization vulnerabilities: What are we missing?". 2015-08-27. <https://www.slideshare.net/_s_n_t/php-unserialization-vulnerabilities-what-are-we-missing>. URL validated: 2023-04-07.

[REF-463] Gabriel Lawrence and Chris Frohoff. "Marshalling Pickles: How deserializing objects can ruin your day". 2015-01-28. <https://www.slideshare.net/frohoff1/appseccali-2015-marshalling-pickles>. URL validated: 2023-04-07.

[REF-464] Heine Deelstra. "Unserializing user-supplied data, a bad idea". 2010-08-25. <https://drupalsun.com/heine/2010/08/25/unserializing-user-supplied-data-bad-idea>. URL validated: 2023-04-07.

[REF-465] Manish S. Saindane. "Black Hat EU 2010 - Attacking Java Serialized Communication". 2010-04-26. <https://www.slideshare.net/msaindane/black-hat-eu-2010-attacking-java-serialized-communication>. URL validated: 2023-04-07.

[REF-466] Nadia Alramli. "Why Python Pickle is Insecure". 2009-09-09. <http://michael-rushanan.blogspot.com/2012/10/why-python-pickle-is-insecure.html>. URL validated: 2023-04-07.

[REF-467] Nelson Elhage. "Exploiting misuse of Python's "pickle"". 2011-03-20. <https://blog.nelhage.com/2011/03/exploiting-pickle/>.

[REF-468] Chris Frohoff. "Deserialize My Shorts: Or How I Learned to Start Worrying and Hate Java Object Deserialization". 2016-03-21. <https://speakerdeck.com/frohoff/owasp-sd-deserialize-my-shorts-or-how-i-learned-to-start-worrying-and-hate-java-object-deserialization>. URL validated: 2023-04-07.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Description, Relationships, Other_Notes, Taxonomy_Mappings
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes, Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Alternate_Terms, Applicable_Platforms, Background_Details, Common_Consequences, Maintenance_Notes, Observed_Examples, Potential_Mitigations, References, Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Observed_Examples, References, Relationships
2017-05-03	CWE Content Team	MITRE
2017-05-03	updated Applicable_Platforms, Demonstrative_Examples, Description, Potential_Mitigations, References
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Modes_of_Introduction, Potential_Mitigations, References, Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Related_Attack_Patterns, Relationships, Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Type
2019-09-19	CWE Content Team	MITRE
2019-09-19	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Observed_Examples, References, Relationships
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Alternate_Terms, Potential_Mitigations
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Relationships
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Applicable_Platforms
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes, Relationships

Weakness ID: 111

View customized information:

Description

When a Java application uses the Java Native Interface (JNI) to call code written in another programming language, it can expose the application to weaknesses in that code, even if those weaknesses cannot occur in Java.

Extended Description

Many safety features that programmers may take for granted do not apply for native code, so you must carefully review all such code for potential problems. The languages used to implement native code may be more susceptible to buffer overflows and other attacks. Native code is unprotected by the security features enforced by the runtime environment, such as strong typing and array bounds checking.

Common Consequences

Scope	Impact	Likelihood
Access Control	Technical Impact: Bypass Protection Mechanism

Potential Mitigations

Phase: Implementation

Implement error handling around the JNI call.

Phase: Implementation

Strategy: Refactoring

Do not use JNI calls if you don't trust the native library.

Phase: Implementation

Strategy: Refactoring

Be reluctant to use JNI calls. A Java API equivalent may exist.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code defines a class named Echo. The class declares one native method (defined below), which uses C to echo commands entered on the console back to the user. The following C code defines the native method implemented in the Echo class:

(bad code)

Example Language: Java

class Echo {

public native void runEcho();
static {

System.loadLibrary("echo");

}
public static void main(String[] args) {

new Echo().runEcho();

}

(bad code)

Example Language: C

#include <jni.h>
#include "Echo.h"//the java class above compiled with javah
#include <stdio.h>

JNIEXPORT void JNICALL
Java_Echo_runEcho(JNIEnv *env, jobject obj)
{

char buf[64];
gets(buf);
printf(buf);

}

Because the example is implemented in Java, it may appear that it is immune to memory issues like buffer overflow vulnerabilities. Although Java does do a good job of making memory operations safe, this protection does not extend to vulnerabilities occurring in source code written in other languages that are accessed using the Java Native Interface. Despite the memory protections offered in Java, the C code in this example is vulnerable to a buffer overflow because it makes use of gets(), which does not check the length of its input.

The Sun Java(TM) Tutorial provides the following description of JNI [See Reference]: The JNI framework lets your native method utilize Java objects in the same way that Java code uses these objects. A native method can create Java objects, including arrays and strings, and then inspect and use these objects to perform its tasks. A native method can also inspect and use objects created by Java application code. A native method can even update Java objects that it created or that were passed to it, and these updated objects are available to the Java application. Thus, both the native language side and the Java side of an application can create, update, and access Java objects and then share these objects between them.

The vulnerability in the example above could easily be detected through a source code audit of the native method implementation. This may not be practical or possible depending on the availability of the C source code and the way the project is built, but in many cases it may suffice. However, the ability to share objects between Java and native methods expands the potential risk to much more insidious cases where improper data handling in Java may lead to unexpected vulnerabilities in native code or unsafe operations in native code corrupt data structures in Java. Vulnerabilities in native code accessed through a Java application are typically exploited in the same manner as they are in applications written in the native language. The only challenge to such an attack is for the attacker to identify that the Java application uses native code to perform certain operations. This can be accomplished in a variety of ways, including identifying specific behaviors that are often implemented with native code or by exploiting a system information exposure in the Java application that reveals its use of JNI [See Reference].

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	859	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 16 - Platform Security (SEC)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1151	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 17. Java Native Interface (JNI)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Unsafe JNI
The CERT Oracle Secure Coding Standard for Java (2011)	SEC08-J		Define wrappers around native methods
SEI CERT Oracle Coding Standard for Java	JNI01-J		Safely invoke standard APIs that perform tasks using the immediate caller's class loader instance (loadLibrary)
SEI CERT Oracle Coding Standard for Java	JNI00-J	Imprecise	Define wrappers around native methods
Software Fault Patterns	SFP3		Use of an improper API

References

[REF-41] Fortify Software. "Fortify Descriptions". <http://vulncat.fortifysoftware.com>.

[REF-42] Beth Stearns. "The Java(TM) Tutorial: The Java Native Interface". Sun Microsystems. 2005. <http://www.eg.bucknell.edu/~mead/Java-tutorial/native1.1/index.html>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Demonstrative_Example, Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, References, Taxonomy_Mappings, Weakness_Ordinalities
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Description, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Potential_Mitigations, References
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships, Type
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Unsafe JNI

Weakness ID: 609

View customized information:

Description

The product uses double-checked locking to access a resource without the overhead of explicit synchronization, but the locking is insufficient.

Extended Description

Double-checked locking refers to the situation where a programmer checks to see if a resource has been initialized, grabs a lock, checks again to see if the resource has been initialized, and then performs the initialization if it has not occurred yet. This should not be done, as it is not guaranteed to work in all languages and on all architectures. In summary, other threads may not be operating inside the synchronous block and are not guaranteed to see the operations execute in the same order as they would appear inside the synchronous block.

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Modify Application Data; Alter Execution Logic

Potential Mitigations

Phase: Implementation

While double-checked locking can be achieved in some languages, it is inherently flawed in Java before 1.5, and cannot be achieved without compromising platform independence. Before Java 1.5, only use of the synchronized keyword is known to work. Beginning in Java 1.5, use of the "volatile" keyword allows double-checked locking to work successfully, although there is some debate as to whether it achieves sufficient performance gains. See references.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	667	Improper Locking
CanPrecede	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	367	Time-of-check Time-of-use (TOCTOU) Race Condition

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	411	Resource Locking Problems

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

It may seem that the following bit of code achieves thread safety while avoiding unnecessary synchronization...

(bad code)

Example Language: Java

if (helper == null) {

synchronized (this) {

if (helper == null) {

helper = new Helper();

}

}
return helper;

The programmer wants to guarantee that only one Helper() object is ever allocated, but does not want to pay the cost of synchronization every time this code is called.

Suppose that helper is not initialized. Then, thread A sees that helper==null and enters the synchronized block and begins to execute:

(bad code)

helper = new Helper();

If a second thread, thread B, takes over in the middle of this call and helper has not finished running the constructor, then thread B may make calls on helper while its fields hold incorrect values.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	853	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 10 - Locking (LCK)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	986	SFP Secondary Cluster: Missing Lock
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1143	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 09. Locking (LCK)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	LCK10-J		Do not use incorrect forms of the double-checked locking idiom
Software Fault Patterns	SFP19		Missing Lock

References

[REF-490] David Bacon et al. "The "Double-Checked Locking is Broken" Declaration". <http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html>.

[REF-491] Jeremy Manson and Brian Goetz. "JSR 133 (Java Memory Model) FAQ". <http://www.cs.umd.edu/~pugh/java/memoryModel/jsr-133-faq.html#dcl>.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 13, "Threading Vulnerabilities", Page 815. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2007-05-07 (CWE Draft 6, 2007-05-07)	Anonymous Tool Vendor (under NDA)
2007-05-07 (CWE Draft 6, 2007-05-07)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Context_Notes
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Demonstrative_Examples
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Relationships
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Relationships
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Taxonomy_Mappings
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, References, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Double Checked Locking

Weakness ID: 462

View customized information:

Description

Duplicate keys in associative lists can lead to non-unique keys being mistaken for an error.

Extended Description

A duplicate key entry -- if the alist is designed properly -- could be used as a constant time replace function. However, duplicate key entries could be inserted by mistake. Because of this ambiguity, duplicate key entries in an association list are not recommended and should not be allowed.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation; Varies by Context

Potential Mitigations

Phase: Architecture and Design

Use a hash table instead of an alist.

Phase: Architecture and Design

Use an alist which checks the uniqueness of hash keys with each entry before inserting the entry.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	694	Use of Multiple Resources with Duplicate Identifier

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Low

Demonstrative Examples

Example 1

The following code adds data to a list and then attempts to sort the data.

(bad code)

Example Language: Python

alist = []
while (foo()): #now assume there is a string data with a key basename

queue.append(basename,data)
queue.sort()

Since basename is not necessarily unique, this may not sort how one would like it to be.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	744	CERT C Secure Coding Standard (2008) Chapter 11 - Environment (ENV)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	878	CERT C++ Secure Coding Section 10 - Environment (ENV)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	977	SFP Secondary Cluster: Design
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Duplicate key in associative list (alist)
CERT C Secure Coding	ENV02-C		Beware of multiple environment variables with the same effective name

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Demonstrative_Examples, Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction, Type
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 575

View customized information:

Description

The product violates the Enterprise JavaBeans (EJB) specification by using AWT/Swing.

Extended Description

The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the product violates the following EJB guideline: "An enterprise bean must not use the AWT functionality to attempt to output information to a display, or to input information from a keyboard." The specification justifies this requirement in the following way: "Most servers do not allow direct interaction between an application program and a keyboard/display attached to the server system."

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Architecture and Design

Do not use AWT/Swing when writing EJBs.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java example is a simple converter class for converting US dollars to Yen. This converter class demonstrates the improper practice of using a stateless session Enterprise JavaBean that implements an AWT Component and AWT keyboard event listener to retrieve keyboard input from the user for the amount of the US dollars to convert to Yen.

(bad code)

Example Language: Java

@Stateless
public class ConverterSessionBean extends Component implements KeyListener, ConverterSessionRemote {

/* member variables for receiving keyboard input using AWT API */

...
private StringBuffer enteredText = new StringBuffer();

/* conversion rate on US dollars to Yen */

private BigDecimal yenRate = new BigDecimal("115.3100");

public ConverterSessionBean() {

super();
/* method calls for setting up AWT Component for receiving keyboard input */

...
addKeyListener(this);

}

public BigDecimal dollarToYen(BigDecimal dollars) {

BigDecimal result = dollars.multiply(yenRate);
return result.setScale(2, BigDecimal.ROUND_DOWN);

}

/* member functions for implementing AWT KeyListener interface */

public void keyTyped(KeyEvent event) {

...

}

public void keyPressed(KeyEvent e) {
}

public void keyReleased(KeyEvent e) {
}

/* member functions for receiving keyboard input and displaying output */

public void paint(Graphics g) {...}

...

}

This use of the AWT and Swing APIs within any kind of Enterprise JavaBean not only violates the restriction of the EJB specification against using AWT or Swing within an EJB but also violates the intended use of Enterprise JavaBeans to separate business logic from presentation logic.

The Stateless Session Enterprise JavaBean should contain only business logic. Presentation logic should be provided by some other mechanism such as Servlets or Java Server Pages (JSP) as in the following Java/JSP example.

(good code)

Example Language: Java

@Stateless
public class ConverterSessionBean implements ConverterSessionRemoteInterface {

/* conversion rate on US dollars to Yen */
private BigDecimal yenRate = new BigDecimal("115.3100");

public ConverterSessionBean() {
}

/* remote method to convert US dollars to Yen */

public BigDecimal dollarToYen(BigDecimal dollars) {

BigDecimal result = dollars.multiply(yenRate);
return result.setScale(2, BigDecimal.ROUND_DOWN);

}

(good code)

Example Language: JSP

<%@ page import="converter.ejb.Converter, java.math.*, javax.naming.*"%>
<%!

private Converter converter = null;
public void jspInit() {

try {

InitialContext ic = new InitialContext();
converter = (Converter) ic.lookup(Converter.class.getName());

} catch (Exception ex) {

System.out.println("Couldn't create converter bean."+ ex.getMessage());

}

}
public void jspDestroy() {

converter = null;

}

%>
<html>

<head><title>Converter</title></head>
<body bgcolor="white">

<h1>Converter</h1>
<hr>
<p>Enter an amount to convert:</p>
<form method="get">

</form>
<%

String amount = request.getParameter("amount");
if ( amount != null && amount.length() > 0 ) {

BigDecimal d = new BigDecimal(amount);
BigDecimal yenAmount = converter.dollarToYen(d);

%>
<p>
<%= amount %> dollars are <%= yenAmount %> Yen.
<p>
<%

}

</body>

</html>

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples, Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 578

View customized information:

Description

The product violates the Enterprise JavaBeans (EJB) specification by using the class loader.

Extended Description

The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the product violates the following EJB guideline: "The enterprise bean must not attempt to create a class loader; obtain the current class loader; set the context class loader; set security manager; create a new security manager; stop the JVM; or change the input, output, and error streams." The specification justifies this requirement in the following way: "These functions are reserved for the EJB container. Allowing the enterprise bean to use these functions could compromise security and decrease the container's ability to properly manage the runtime environment."

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity Availability Other	Technical Impact: Execute Unauthorized Code or Commands; Varies by Context

Potential Mitigations

Phases: Architecture and Design; Implementation

Do not use the Class Loader when writing EJBs.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java example is a simple stateless Enterprise JavaBean that retrieves the interest rate for the number of points for a mortgage. The interest rates for various points are retrieved from an XML document on the local file system, and the EJB uses the Class Loader for the EJB class to obtain the XML document from the local file system as an input stream.

(bad code)

Example Language: Java

@Stateless
public class InterestRateBean implements InterestRateRemote {

private Document interestRateXMLDocument = null;

public InterestRateBean() {

try {

// get XML document from the local filesystem as an input stream

// using the ClassLoader for this class
ClassLoader loader = this.getClass().getClassLoader();
InputStream in = loader.getResourceAsStream(Constants.INTEREST_RATE_FILE);

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

DocumentBuilder db = dbf.newDocumentBuilder();
interestRateXMLDocument = db.parse(interestRateFile);

} catch (IOException ex) {...}

}

public BigDecimal getInterestRate(Integer points) {

return getInterestRateFromXML(points);

}

/* member function to retrieve interest rate from XML document on the local file system */

private BigDecimal getInterestRateFromXML(Integer points) {...}

}

This use of the Java Class Loader class within any kind of Enterprise JavaBean violates the restriction of the EJB specification against obtaining the current class loader as this could compromise the security of the application using the EJB.

Example 2

An EJB is also restricted from creating a custom class loader and creating a class and instance of a class from the class loader, as shown in the following example.

(bad code)

Example Language: Java

@Stateless
public class LoaderSessionBean implements LoaderSessionRemote {

public LoaderSessionBean() {

try {

ClassLoader loader = new CustomClassLoader();
Class c = loader.loadClass("someClass");
Object obj = c.newInstance();
/* perform some task that uses the new class instance member variables or functions */
...

} catch (Exception ex) {...}

}

public class CustomClassLoader extends ClassLoader {

}

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples, Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 576

View customized information:

Description

The product violates the Enterprise JavaBeans (EJB) specification by using the java.io package.

Extended Description

The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the product violates the following EJB guideline: "An enterprise bean must not use the java.io package to attempt to access files and directories in the file system." The specification justifies this requirement in the following way: "The file system APIs are not well-suited for business components to access data. Business components should use a resource manager API, such as JDBC, to store data."

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Implementation

Do not use Java I/O when writing EJBs.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java example is a simple stateless Enterprise JavaBean that retrieves the interest rate for the number of points for a mortgage. In this example, the interest rates for various points are retrieved from an XML document on the local file system, and the EJB uses the Java I/O API to retrieve the XML document from the local file system.

(bad code)

Example Language: Java

@Stateless
public class InterestRateBean implements InterestRateRemote {

private Document interestRateXMLDocument = null;
private File interestRateFile = null;

public InterestRateBean() {

try {

/* get XML document from the local filesystem */
interestRateFile = new File(Constants.INTEREST_RATE_FILE);

if (interestRateFile.exists())
{

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
interestRateXMLDocument = db.parse(interestRateFile);

}

} catch (IOException ex) {...}

}

public BigDecimal getInterestRate(Integer points) {

return getInterestRateFromXML(points);

}

/* member function to retrieve interest rate from XML document on the local file system */

private BigDecimal getInterestRateFromXML(Integer points) {...}

}

This use of the Java I/O API within any kind of Enterprise JavaBean violates the EJB specification by using the java.io package for accessing files within the local filesystem.

An Enterprise JavaBean should use a resource manager API for storing and accessing data. In the following example, the private member function getInterestRateFromXMLParser uses an XML parser API to retrieve the interest rates.

(good code)

Example Language: Java

@Stateless
public class InterestRateBean implements InterestRateRemote {

public InterestRateBean() {
}

public BigDecimal getInterestRate(Integer points) {

return getInterestRateFromXMLParser(points);

}

/* member function to retrieve interest rate from XML document using an XML parser API */

private BigDecimal getInterestRateFromXMLParser(Integer points) {...}

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 577

View customized information:

Description

The product violates the Enterprise JavaBeans (EJB) specification by using sockets.

Extended Description

The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the product violates the following EJB guideline: "An enterprise bean must not attempt to listen on a socket, accept connections on a socket, or use a socket for multicast." The specification justifies this requirement in the following way: "The EJB architecture allows an enterprise bean instance to be a network socket client, but it does not allow it to be a network server. Allowing the instance to become a network server would conflict with the basic function of the enterprise bean-- to serve the EJB clients."

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phases: Architecture and Design; Implementation

Do not use Sockets when writing EJBs.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java example is a simple stateless Enterprise JavaBean that retrieves stock symbols and stock values. The Enterprise JavaBean creates a socket and listens for and accepts connections from clients on the socket.

(bad code)

Example Language: Java

@Stateless
public class StockSymbolBean implements StockSymbolRemote {

ServerSocket serverSocket = null;
Socket clientSocket = null;

public StockSymbolBean() {

try {

serverSocket = new ServerSocket(Constants.SOCKET_PORT);

} catch (IOException ex) {...}

try {

clientSocket = serverSocket.accept();

} catch (IOException e) {...}

}

public String getStockSymbol(String name) {...}

public BigDecimal getStockValue(String symbol) {...}

private void processClientInputFromSocket() {...}

}

And the following Java example is similar to the previous example but demonstrates the use of multicast socket connections within an Enterprise JavaBean.

(bad code)

Example Language: Java

@Stateless
public class StockSymbolBean extends Thread implements StockSymbolRemote {

ServerSocket serverSocket = null;
Socket clientSocket = null;
boolean listening = false;

public StockSymbolBean() {

try {

serverSocket = new ServerSocket(Constants.SOCKET_PORT);

} catch (IOException ex) {...}

listening = true;
while(listening) {

start();

}

}

public String getStockSymbol(String name) {...}

public BigDecimal getStockValue(String symbol) {...}

public void run() {

try {

clientSocket = serverSocket.accept();

} catch (IOException e) {...}
...

}

The previous two examples within any type of Enterprise JavaBean violate the EJB specification by attempting to listen on a socket, accepting connections on a socket, or using a socket for multicast.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples, Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 574

View customized information:

Description

The product violates the Enterprise JavaBeans (EJB) specification by using thread synchronization primitives.

Extended Description

The Enterprise JavaBeans specification requires that every bean provider follow a set of programming guidelines designed to ensure that the bean will be portable and behave consistently in any EJB container. In this case, the product violates the following EJB guideline: "An enterprise bean must not use thread synchronization primitives to synchronize execution of multiple instances." The specification justifies this requirement in the following way: "This rule is required to ensure consistent runtime semantics because while some EJB containers may use a single JVM to execute all enterprise bean's instances, others may distribute the instances across multiple JVMs."

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Implementation

Do not use Synchronization Primitives when writing EJBs.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	821	Incorrect Synchronization

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example a Customer Entity EJB provides access to customer information in a database for a business application.

(bad code)

Example Language: Java

@Entity
public class Customer implements Serializable {

private String id;
private String firstName;
private String lastName;
private Address address;

public Customer() {...}

public Customer(String id, String firstName, String lastName) {...}

@Id
public String getCustomerId() {...}

public synchronized void setCustomerId(String id) {...}

public String getFirstName() {...}

public synchronized void setFirstName(String firstName) {...}

public String getLastName() {...}

public synchronized void setLastName(String lastName) {...}

@OneToOne()
public Address getAddress() {...}

public synchronized void setAddress(Address address) {...}

}

However, the customer entity EJB uses the synchronized keyword for the set methods to attempt to provide thread safe synchronization for the member variables. The use of synchronized methods violate the restriction of the EJB specification against the use synchronization primitives within EJBs. Using synchronization primitives may cause inconsistent behavior of the EJB when used within different EJB containers.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Demonstrative_Examples
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Relationships
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 585

View customized information:

Description

The product contains an empty synchronized block.

Extended Description

An empty synchronized block does not actually accomplish any synchronization and may indicate a troubled section of code. An empty synchronized block can occur because code no longer needed within the synchronized block is commented out without removing the synchronized block.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Other An empty synchronized block will wait until nobody else is using the synchronizer being specified. While this may be part of the desired behavior, because you haven't protected the subsequent code by placing it inside the synchronized block, nothing is stopping somebody else from modifying whatever it was you were waiting for while you run the subsequent code.

Potential Mitigations

Phase: Implementation

When you come across an empty synchronized statement, or a synchronized statement in which the code has been commented out, try to determine what the original intentions were and whether or not the synchronized block is still necessary.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1071	Empty Code Block

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code attempts to synchronize on an object, but does not execute anything in the synchronized block. This does not actually accomplish anything and may be a sign that a programmer is wrestling with synchronization but has not yet achieved the result they intend.

(bad code)

Example Language: Java

synchronized(this) { }

Instead, in a correct usage, the synchronized statement should contain procedures that access or modify data that is exposed to multiple threads. For example, consider a scenario in which several threads are accessing student records at the same time. The method which sets the student ID to a new value will need to make sure that nobody else is accessing this data at the same time and will require synchronization.

(good code)

public void setID(int ID){

synchronized(this){

this.ID = ID;

}

Weakness Ordinalities

Ordinality	Description
Indirect	(where the weakness is a quality issue that might indirectly make it easier to introduce security-relevant weaknesses or make them more difficult to detect)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	987	SFP Secondary Cluster: Multiple Locks/Unlocks
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP21		Multiple locks/unlocks

References

[REF-478] "Intrinsic Locks and Synchronization (in Java)". <https://docs.oracle.com/javase/tutorial/essential/concurrency/locksync.html>. URL validated: 2023-04-07.

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Common_Consequences, Demonstrative_Examples, Description, Other_Notes, Potential_Mitigations, References
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Weakness_Ordinalities
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships, Type
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, References, Relationships, Type
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples

Weakness ID: 586

View customized information:

Description

The product makes an explicit call to the finalize() method from outside the finalizer.

Extended Description

While the Java Language Specification allows an object's finalize() method to be called from outside the finalizer, doing so is usually a bad idea. For example, calling finalize() explicitly means that finalize() will be called more than once: the first time will be the explicit call and the last time will be the call that is made after the object is garbage collected.

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Unexpected State; Quality Degradation

Potential Mitigations

Phases: Implementation; Testing

Do not make explicit calls to finalize(). Use static analysis tools to spot such instances.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1076	Insufficient Adherence to Expected Conventions
PeerOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	675	Multiple Operations on Resource in Single-Operation Context

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1006	Bad Coding Practices

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code fragment calls finalize() explicitly:

(bad code)

Example Language: Java

// time to clean up
widget.finalize();

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	850	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 7 - Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1140	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 06. Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	MET12-J		Do not use finalizers
Software Fault Patterns	SFP3		Use of an improper API

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Name, Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings, Weakness_Ordinalities
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Type
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-09-09	Explicit Call to Finalize

Weakness ID: 583

View customized information:

Description

The product violates secure coding principles for mobile code by declaring a finalize() method public.

Extended Description

A product should never call finalize explicitly, except to call super.finalize() inside an implementation of finalize(). In mobile code situations, the otherwise error prone practice of manual garbage collection can become a security threat if an attacker can maliciously invoke a finalize() method because it is declared with public access.

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity Availability	Technical Impact: Alter Execution Logic; Execute Unauthorized Code or Commands; Modify Application Data

Potential Mitigations

Phase: Implementation

If you are using finalize() as it was designed, there is no reason to declare finalize() with anything other than protected access.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following Java Applet code mistakenly declares a public finalize() method.

(bad code)

Example Language: Java

public final class urlTool extends Applet {

public void finalize() {

...

}
...

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	850	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 7 - Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1140	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 06. Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	MET12-J		Do not use finalizers
Software Fault Patterns	SFP28		Unexpected access points

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Description, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Demonstrative_Examples, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Mobile Code: Public Finalize Method

Weakness ID: 568

View customized information:

Description

The product contains a finalize() method that does not call super.finalize().

Extended Description

The Java Language Specification states that it is a good practice for a finalize() method to call super.finalize().

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Implementation

Call the super.finalize() method.

Phase: Testing

Use static analysis tools to spot such issues in your code.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	459	Incomplete Cleanup

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following method omits the call to super.finalize().

(bad code)

Example Language: Java

protected void finalize() {

discardNative();

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	850	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 7 - Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1140	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 06. Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	MET12-J		Do not use finalizers
Software Fault Patterns	SFP28		Unexpected access points

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Description, Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Erroneous Finalize Method

Weakness ID: 209

View customized information:

Description

The product generates an error message that includes sensitive information about its environment, users, or associated data.

Extended Description

The sensitive information may be valuable information on its own (such as a password), or it may be useful for launching other, more serious attacks. The error message may be created in different ways:

self-generated: the source code explicitly constructs the error message and delivers it
externally-generated: the external environment, such as a language interpreter, handles the error and constructs its own message, whose contents are not under direct control by the programmer

An attacker may use the contents of error messages to help launch another, more focused attack. For example, an attempt to exploit a path traversal weakness (CWE-22) might yield the full pathname of the installed application. In turn, this could be used to select the proper number of ".." sequences to navigate to the targeted file. An attack using SQL injection (CWE-89) might not initially succeed, but an error message could reveal the malformed query, which would expose query logic and possibly even passwords or other sensitive information used within the query.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data Often this will either reveal sensitive information which may be used for a later attack or private information stored in the server.

Potential Mitigations

Phase: Implementation

Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.

If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.

Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.

Phase: Implementation

Handle exceptions internally and do not display errors containing potentially sensitive information to a user.

Phase: Implementation

Strategy: Attack Surface Reduction

Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.

Effectiveness: Defense in Depth

Note: This makes it easier to spot places in the code where data is being used that is unencrypted.

Phases: Implementation; Build and Compilation

Strategy: Compilation or Build Hardening

Debugging information should not make its way into a production release.

Phases: Implementation; Build and Compilation

Strategy: Environment Hardening

Debugging information should not make its way into a production release.

Phase: System Configuration

Where available, configure the environment to use less verbose error messages. For example, in PHP, disable the display_errors setting during configuration, or at runtime using the error_reporting() function.

Phase: System Configuration

Create default error pages or messages that do not leak any information.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	755	Improper Handling of Exceptional Conditions
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	200	Exposure of Sensitive Information to an Unauthorized Actor
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	210	Self-generated Error Message Containing Sensitive Information
ParentOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	211	Externally-Generated Error Message Containing Sensitive Information
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	550	Server-generated Error Message Containing Sensitive Information
PeerOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1295	Debug Messages Revealing Unnecessary Information
CanFollow	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	600	Uncaught Exception in Servlet
CanFollow	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	756	Missing Custom Error Page

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	199	Information Management Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	389	Error Conditions, Return Values, Status Codes

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	200	Exposure of Sensitive Information to an Unauthorized Actor

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1015	Limit Access

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation	REALIZATION: This weakness is caused during implementation of an architectural security tactic.
System Configuration
Operation

Applicable Platforms

Languages

PHP (Often Prevalent)

Java (Often Prevalent)

Class: Not Language-Specific (Undetermined Prevalence)

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

In the following example, sensitive information might be printed depending on the exception that occurs.

(bad code)

Example Language: Java

try {

/.../

}
catch (Exception e) {

System.out.println(e);

}

If an exception related to SQL is handled by the catch, then the output might contain sensitive information such as SQL query structure or private information. If this output is redirected to a web user, this may represent a security problem.

Example 2

This code tries to open a database connection, and prints any exceptions that occur.

(bad code)

Example Language: PHP

try {

openDbConnection();

}
//print exception message that includes exception message and configuration file location
catch (Exception $e) {

echo 'Caught exception: ', $e->getMessage(), '\n';
echo 'Check credentials in config file at: ', $Mysql_config_location, '\n';

}

If an exception occurs, the printed message exposes the location of the configuration file the script is using. An attacker can use this information to target the configuration file (perhaps exploiting a Path Traversal weakness). If the file can be read, the attacker could gain credentials for accessing the database. The attacker may also be able to replace the file with a malicious one, causing the application to use an arbitrary database.

Example 3

The following code generates an error message that leaks the full pathname of the configuration file.

(bad code)

Example Language: Perl

$ConfigDir = "/home/myprog/config";
$uname = GetUserInput("username");

# avoid CWE-22, CWE-78, others.
ExitError("Bad hacker!") if ($uname !~ /^\w+$/);
$file = "$ConfigDir/$uname.txt";
if (! (-e $file)) {

ExitError("Error: $file does not exist");

}
...

If this code is running on a server, such as a web application, then the person making the request should not know what the full pathname of the configuration directory is. By submitting a username that does not produce a $file that exists, an attacker could get this pathname. It could then be used to exploit path traversal or symbolic link following problems that may exist elsewhere in the application.

Example 4

In the example below, the method getUserBankAccount retrieves a bank account object from a database using the supplied username and account number to query the database. If an SQLException is raised when querying the database, an error message is created and output to a log file.

(bad code)

Example Language: Java

public BankAccount getUserBankAccount(String username, String accountNumber) {

BankAccount userAccount = null;
String query = null;
try {

if (isAuthorizedUser(username)) {

query = "SELECT * FROM accounts WHERE owner = "
+ username + " AND accountID = " + accountNumber;
DatabaseManager dbManager = new DatabaseManager();
Connection conn = dbManager.getConnection();
Statement stmt = conn.createStatement();
ResultSet queryResult = stmt.executeQuery(query);
userAccount = (BankAccount)queryResult.getObject(accountNumber);

}

} catch (SQLException ex) {

String logMessage = "Unable to retrieve account information from database,\nquery: " + query;
Logger.getLogger(BankManager.class.getName()).log(Level.SEVERE, logMessage, ex);

}
return userAccount;

}

The error message that is created includes information about the database query that may contain sensitive information about the database or query logic. In this case, the error message will expose the table name and column names used in the database. This data could be used to simplify other attacks, such as SQL injection (CWE-89) to directly access the database.

Observed Examples

Reference	Description
CVE-2008-2049	POP3 server reveals a password in an error message after multiple APOP commands are sent. Might be resultant from another weakness.
CVE-2007-5172	Program reveals password in error message if attacker can trigger certain database errors.
CVE-2008-4638	Composite: application running with high privileges (CWE-250) allows user to specify a restricted file to process, which generates a parsing error that leaks the contents of the file (CWE-209).
CVE-2008-1579	Existence of user names can be determined by requesting a nonexistent blog and reading the error message.
CVE-2007-1409	Direct request to library file in web application triggers pathname leak in error message.
CVE-2008-3060	Malformed input to login page causes leak of full path when IMAP call fails.
CVE-2005-0603	Malformed regexp syntax leads to information exposure in error message.
CVE-2017-9615	verbose logging stores admin credentials in a world-readablelog file
CVE-2018-1999036	SSH password for private key stored in build log

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)
Resultant	(where the weakness is typically related to the presence of some other weaknesses)

Detection Methods

Manual Analysis

This weakness generally requires domain-specific interpretation using manual analysis. However, the number of potential error conditions may be too large to cover completely within limited time constraints.

Effectiveness: High

Automated Analysis

Automated methods may be able to detect certain idioms automatically, such as exposed stack traces or pathnames, but violation of business rules or privacy requirements is not typically feasible.

Effectiveness: Moderate

Automated Dynamic Analysis

Error conditions may be triggered with a stress-test by calling the software simultaneously from a large number of threads or processes, and look for evidence of any unexpected behavior.

Effectiveness: Moderate

Manual Dynamic Analysis

Identify error conditions that are not likely to occur during normal usage and trigger them. For example, run the program under low memory conditions, run with insufficient privileges or permissions, interrupt a transaction before it is completed, or disable connectivity to basic network services such as DNS. Monitor the software for any unexpected behavior. If you trigger an unhandled exception or similar error that was discovered and handled by the application's environment, it may still indicate unexpected conditions that were not handled by the application itself.

Automated Static Analysis

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	717	OWASP Top Ten 2007 Category A6 - Information Leakage and Improper Error Handling
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	728	OWASP Top Ten 2004 Category A7 - Improper Error Handling
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	731	OWASP Top Ten 2004 Category A10 - Insecure Configuration Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	751	2009 Top 25 - Insecure Interaction Between Components
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	801	2010 Top 25 - Insecure Interaction Between Components
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	815	OWASP Top Ten 2010 Category A6 - Security Misconfiguration
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	867	2011 Top 25 - Weaknesses On the Cusp
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	880	CERT C++ Secure Coding Section 12 - Exceptions and Error Handling (ERR)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	933	OWASP Top Ten 2013 Category A5 - Security Misconfiguration
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1032	OWASP Top Ten 2017 Category A6 - Security Misconfiguration
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1348	OWASP Top Ten 2021 Category A04:2021 - Insecure Design
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1417	Comprehensive Categorization: Sensitive Information Exposure

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Accidental leaking of sensitive information through error messages
OWASP Top Ten 2007	A6	CWE More Specific	Information Leakage and Improper Error Handling
OWASP Top Ten 2004	A7	CWE More Specific	Improper Error Handling
OWASP Top Ten 2004	A10	CWE More Specific	Insecure Configuration Management
The CERT Oracle Secure Coding Standard for Java (2011)	ERR01-J		Do not allow exceptions to expose sensitive information
Software Fault Patterns	SFP23		Exposed Data

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-215	Fuzzing for application mapping
CAPEC-463	Padding Oracle Crypto Attack
CAPEC-54	Query System for Information
CAPEC-7	Blind SQL Injection

References

[REF-174] Web Application Security Consortium. "Information Leakage". <http://projects.webappsec.org/w/page/13246936/Information%20Leakage>. URL validated: 2023-04-07.

[REF-175] Brian Chess and Jacob West. "Secure Programming with Static Analysis". Section 9.2, Page 326. Addison-Wesley. 2007.

[REF-176] Michael Howard and David LeBlanc. "Writing Secure Code". Chapter 16, "General Good Practices." Page 415. 1st Edition. Microsoft Press. 2001-11-13.

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 11: Failure to Handle Errors Correctly." Page 183. McGraw-Hill. 2010.

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 12: Information Leakage." Page 191. McGraw-Hill. 2010.

[REF-179] Johannes Ullrich. "Top 25 Series - Rank 16 - Information Exposure Through an Error Message". SANS Software Security Institute. 2010-03-17. <http://software-security.sans.org/blog/2010/03/17/top-25-series-rank-16-information-exposure-through-an-error-message>.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 3, "Overly Verbose Error Messages", Page 75. 1st Edition. Addison Wesley. 2006.

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Contributions
Contribution Date	Contributor	Organization
2022-07-11	Nick Johnston
2022-07-11	Identified incorrect language tag in demonstrative example.
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-15		Veracode
2008-08-15	Suggested OWASP Top Ten 2004 mapping
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Relationships
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Demonstrative_Examples, Description, Name, Observed_Examples, Other_Notes, Potential_Mitigations, Relationships, Time_of_Introduction
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Demonstrative_Examples, Potential_Mitigations, Relationships
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples, Name, Potential_Mitigations, References, Time_of_Introduction
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Detection_Factors, References, Relationships
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Related_Attack_Patterns
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Common_Consequences, Detection_Factors, Potential_Mitigations, References
2010-09-09		Veracode
2010-09-09	Suggested OWASP Top Ten mapping
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Potential_Mitigations, Relationships
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples, Observed_Examples, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Relationships
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Related_Attack_Patterns, Relationships
2013-07-17	CWE Content Team	MITRE
2013-07-17	updated References
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Applicable_Platforms, Modes_of_Introduction, References, Relationships, Taxonomy_Mappings
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated References, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Relationships
2019-09-19	CWE Content Team	MITRE
2019-09-19	updated Demonstrative_Examples, Observed_Examples
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Applicable_Platforms, Description, Name, Observed_Examples, References, Relationships, Weakness_Ordinalities
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Potential_Mitigations, Related_Attack_Patterns
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Relationships
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Demonstrative_Examples
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2009-01-12	Error Message Information Leaks

2009-12-28	Error Message Information Leak

2020-02-24	Information Exposure Through an Error Message

Weakness ID: 460

View customized information:

Description

The product does not clean up its state or incorrectly cleans up its state when an exception is thrown, leading to unexpected state or control flow.

Extended Description

Often, when functions or loops become complicated, some level of resource cleanup is needed throughout execution. Exceptions can disturb the flow of the code and prevent the necessary cleanup from happening.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Varies by Context The code could be left in a bad state.

Potential Mitigations

Phase: Implementation

If one breaks from a loop or function by throwing an exception, make sure that cleanup happens or that you should exit the program. Use throwing exceptions sparsely.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	755	Improper Handling of Exceptional Conditions
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	459	Incomplete Cleanup

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1012	Cross Cutting

Modes Of Introduction

Phase	Note
Implementation	REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following example demonstrates the weakness.

(bad code)

Example Language: Java

public class foo {

public static final void main( String args[] ) {

boolean returnValue;
returnValue=doStuff();

}
public static final boolean doStuff( ) {

boolean threadLock;
boolean truthvalue=true;
try {

while(
//check some condition
) {

threadLock=true; //do some stuff to truthvalue
threadLock=false;

}

}
catch (Exception e){

System.err.println("You did something bad");
if (something) return truthvalue;

}
return truthvalue;

}

In this case, a thread might be left locked accidentally.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	880	CERT C++ Secure Coding Section 12 - Exceptions and Error Handling (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	961	SFP Secondary Cluster: Incorrect Exception Behavior
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1141	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 07. Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1181	SEI CERT Perl Coding Standard - Guidelines 03. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Improper cleanup on thrown exception
The CERT Oracle Secure Coding Standard for Java (2011)	ERR03-J		Restore prior object state on method failure
The CERT Oracle Secure Coding Standard for Java (2011)	ERR05-J		Do not let checked exceptions escape from a finally block
SEI CERT Perl Coding Standard	EXP31-PL	Imprecise	Do not suppress or ignore exceptions

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Description
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Modes_of_Introduction, Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Type
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples

Weakness ID: 95

View customized information:

Description

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes code syntax before using the input in a dynamic evaluation call (e.g. "eval").

Extended Description

This may allow an attacker to execute arbitrary code, or at least modify what code can be executed.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Files or Directories; Read Application Data The injected code could access restricted data / files.
Access Control	Technical Impact: Bypass Protection Mechanism In some cases, injectable code controls authentication; this may lead to a remote vulnerability.
Access Control	Technical Impact: Gain Privileges or Assume Identity Injected code can access resources that the attacker is directly prevented from accessing.
Integrity Confidentiality Availability Other	Technical Impact: Execute Unauthorized Code or Commands Code injection attacks can lead to loss of data integrity in nearly all cases as the control-plane data injected is always incidental to data recall or writing. Additionally, code injection can often result in the execution of arbitrary code.
Non-Repudiation	Technical Impact: Hide Activities Often the actions performed by injected control code are unlogged.

Potential Mitigations

Phases: Architecture and Design; Implementation

If possible, refactor your code so that it does not need to use eval() at all.

Phase: Implementation

Strategy: Input Validation

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.

When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."

Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

Phase: Implementation

Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180, CWE-181). Make sure that your application does not inadvertently decode the same input twice (CWE-174). Such errors could be used to bypass allowlist schemes by introducing dangerous inputs after they have been checked. Use libraries such as the OWASP ESAPI Canonicalization control.

Consider performing repeated canonicalization until your input does not change any more. This will avoid double-decoding and similar scenarios, but it might inadvertently modify inputs that are allowed to contain properly-encoded dangerous content.

Phase: Implementation

For Python programs, it is frequently encouraged to use the ast.literal_eval() function instead of eval, since it is intentionally designed to avoid executing code. However, an adversary could still cause excessive memory or stack consumption via deeply nested structures [REF-1372], so the python documentation discourages use of ast.literal_eval() on untrusted data [REF-1373].

Effectiveness: Discouraged Common Practice

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	94	Improper Control of Generation of Code ('Code Injection')

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1019	Validate Inputs

Modes Of Introduction

Phase	Note
Implementation	REALIZATION: This weakness is caused during implementation of an architectural security tactic.
Implementation	This weakness is prevalent in handler/dispatch procedures that might want to invoke a large number of functions, or set a large number of variables.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

Python (Undetermined Prevalence)

Perl (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Ruby (Undetermined Prevalence)

Class: Interpreted (Undetermined Prevalence)

Technologies

AI/ML (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

edit-config.pl: This CGI script is used to modify settings in a configuration file.

(bad code)

Example Language: Perl

use CGI qw(:standard);

sub config_file_add_key {

my ($fname, $key, $arg) = @_;
# code to add a field/key to a file goes here

}

sub config_file_set_key {

my ($fname, $key, $arg) = @_;
# code to set key to a particular file goes here

}

sub config_file_delete_key {

my ($fname, $key, $arg) = @_;
# code to delete key from a particular file goes here

}

sub handleConfigAction {

my ($fname, $action) = @_;
my $key = param('key');
my $val = param('val');
# this is super-efficient code, especially if you have to invoke
# any one of dozens of different functions!

my $code = "config_file_$action_key(\$fname, \$key, \$val);";
eval($code);

}

$configfile = "/home/cwe/config.txt";
print header;
if (defined(param('action'))) {

handleConfigAction($configfile, param('action'));

}
else {

print "No action specified!\n";

}

The script intends to take the 'action' parameter and invoke one of a variety of functions based on the value of that parameter - config_file_add_key(), config_file_set_key(), or config_file_delete_key(). It could set up a conditional to invoke each function separately, but eval() is a powerful way of doing the same thing in fewer lines of code, especially when a large number of functions or variables are involved. Unfortunately, in this case, the attacker can provide other values in the action parameter, such as:

(attack code)

add_key(",","); system("/bin/ls");

This would produce the following string in handleConfigAction():

(result)

config_file_add_key(",","); system("/bin/ls");

Any arbitrary Perl code could be added after the attacker has "closed off" the construction of the original function call, in order to prevent parsing errors from causing the malicious eval() to fail before the attacker's payload is activated. This particular manipulation would fail after the system() call, because the "_key(\$fname, \$key, \$val)" portion of the string would cause an error, but this is irrelevant to the attack because the payload has already been activated.

Example 2

This simple script asks a user to supply a list of numbers as input and adds them together.

(bad code)

Example Language: Python

def main():

sum = 0
numbers = eval(input("Enter a space-separated list of numbers: "))
for num in numbers:

sum = sum + num

print(f"Sum of {numbers} = {sum}")

main()

The eval() function can take the user-supplied list and convert it into a Python list object, therefore allowing the programmer to use list comprehension methods to work with the data. However, if code is supplied to the eval() function, it will execute that code. For example, a malicious user could supply the following string:

(attack code)

__import__('subprocess').getoutput('rm -r *')

This would delete all the files in the current directory. For this reason, it is not recommended to use eval() with untrusted input.

A way to accomplish this without the use of eval() is to apply an integer conversion on the input within a try/except block. If the user-supplied input is not numeric, this will raise a ValueError. By avoiding eval(), there is no opportunity for the input string to be executed as code.

(good code)

Example Language: Python

def main():

sum = 0
numbers = input("Enter a space-separated list of numbers: ").split(" ")
try:

for num in numbers:

sum = sum + int(num)

print(f"Sum of {numbers} = {sum}")

except ValueError:

print("Error: invalid input")

main()

An alternative, commonly-cited mitigation for this kind of weakness is to use the ast.literal_eval() function, since it is intentionally designed to avoid executing code. However, an adversary could still cause excessive memory or stack consumption via deeply nested structures [REF-1372], so the python documentation discourages use of ast.literal_eval() on untrusted data [REF-1373].

Observed Examples

Reference	Description
CVE-2024-4181	Framework for LLM applications allows eval injection via a crafted response from a hosting provider.
CVE-2022-2054	Python compiler uses eval() to execute malicious strings as Python code.
CVE-2021-22204	Chain: regex in EXIF processor code does not correctly determine where a string ends (CWE-625), enabling eval injection (CWE-95), as exploited in the wild per CISA KEV.
CVE-2021-22205	Chain: backslash followed by a newline can bypass a validation step (CWE-20), leading to eval injection (CWE-95), as exploited in the wild per CISA KEV.
CVE-2008-5071	Eval injection in PHP program.
CVE-2002-1750	Eval injection in Perl program.
CVE-2008-5305	Eval injection in Perl program using an ID that should only contain hyphens and numbers.
CVE-2002-1752	Direct code injection into Perl eval function.
CVE-2002-1753	Eval injection in Perl program.
CVE-2005-1527	Direct code injection into Perl eval function.
CVE-2005-2837	Direct code injection into Perl eval function.
CVE-2005-1921	MFV. code injection into PHP eval statement using nested constructs that should not be nested.
CVE-2005-2498	MFV. code injection into PHP eval statement using nested constructs that should not be nested.
CVE-2005-3302	Code injection into Python eval statement from a field in a formatted file.
CVE-2007-1253	Eval injection in Python program.
CVE-2001-1471	chain: Resultant eval injection. An invalid value prevents initialization of variables, which can be modified by attacker and later injected into PHP eval statement.
CVE-2007-2713	Chain: Execution after redirect triggers eval injection.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	714	OWASP Top Ten 2007 Category A3 - Malicious File Execution
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	727	OWASP Top Ten 2004 Category A6 - Injection Flaws
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1179	SEI CERT Perl Coding Standard - Guidelines 01. Input Validation and Data Sanitization (IDS)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1347	OWASP Top Ten 2021 Category A03:2021 - Injection
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1409	Comprehensive Categorization: Injection

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Other

Factors: special character errors can play a role in increasing the variety of code that can be injected, although some vulnerabilities do not require special characters at all, e.g. when a single function without arguments can be referenced and a terminator character is not necessary.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Direct Dynamic Code Evaluation ('Eval Injection')
OWASP Top Ten 2007	A3	CWE More Specific	Malicious File Execution
OWASP Top Ten 2004	A6	CWE More Specific	Injection Flaws
Software Fault Patterns	SFP24		Tainted input to command
SEI CERT Perl Coding Standard	IDS35-PL	Exact	Do not invoke the eval form with a string argument

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-35	Leverage Executable Code in Non-Executable Files

References

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 18, "Inline Evaluation", Page 1095. 1st Edition. Addison Wesley. 2006.

[REF-1372] "How ast.literal_eval can cause memory exhaustion". Reddit. 2022-12-14. <https://www.reddit.com/r/learnpython/comments/zmbhcf/how_astliteral_eval_can_cause_memory_exhaustion/>. URL validated: 2023-11-03.

[REF-1373] "ast - Abstract Syntax Trees". ast.literal_eval(node_or_string). Python. 2023-11-02. <https://docs.python.org/3/library/ast.html#ast.literal_eval>. URL validated: 2023-11-03.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	PLOVER
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-15		Veracode
2008-08-15	Suggested OWASP Top Ten 2004 mapping
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Description, Modes_of_Introduction, Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Description, Observed_Examples, Other_Notes, Research_Gaps
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Alternate_Terms, Applicable_Platforms, Demonstrative_Examples, Description, Name, References
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Potential_Mitigations
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Description, Name
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Demonstrative_Examples, References, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Observed_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Modes_of_Introduction, References, Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Type
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Potential_Mitigations, Relationships
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Potential_Mitigations
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Research_Gaps
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Observed_Examples
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Observed_Examples
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Demonstrative_Examples, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Demonstrative_Examples, Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples, Potential_Mitigations, References
2024-07-16 (CWE 4.15, 2024-07-16)	CWE Content Team	MITRE
2024-07-16 (CWE 4.15, 2024-07-16)	updated Applicable_Platforms, Observed_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Direct Dynamic Code Evaluation ('Eval Injection')

2009-05-27	Insufficient Control of Directives in Dynamically Evaluated Code (aka 'Eval Injection')

2010-06-21	Improper Sanitization of Directives in Dynamically Evaluated Code ('Eval Injection')

Weakness ID: 1336

View customized information:

Description

The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine.

Extended Description

Many web applications use template engines that allow developers to insert externally-influenced values into free text or messages in order to generate a full web page, document, message, etc. Such engines include Twig, Jinja2, Pug, Java Server Pages, FreeMarker, Velocity, ColdFusion, Smarty, and many others - including PHP itself. Some CMS (Content Management Systems) also use templates.

Template engines often have their own custom command or expression language. If an attacker can influence input into a template before it is processed, then the attacker can invoke arbitrary expressions, i.e. perform injection attacks. For example, in some template languages, an attacker could inject the expression "{{7*7}}" and determine if the output returns "49" instead. The syntax varies depending on the language.

In some cases, XSS-style attacks can work, which can obscure the root cause if the developer does not closely investigate the root cause of the error.

Template engines can be used on the server or client, so both "sides" could be affected by injection. The mechanisms of attack or the affected technologies might be different, but the mistake is fundamentally the same.

Alternate Terms

Server-Side Template Injection / SSTI:	This term is used for injection into template engines being used by a server.
Client-Side Template Injection / CSTI:	This term is used for injection into template engines being used by a client.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Execute Unauthorized Code or Commands

Potential Mitigations

Phase: Architecture and Design

Choose a template engine that offers a sandbox or restricted mode, or at least limits the power of any available expressions, function calls, or commands.

Phase: Implementation

Use the template engine's sandbox or restricted mode, if available.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	94	Improper Control of Generation of Code ('Code Injection')
PeerOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	917	Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

Modes Of Introduction

Phase	Note
Architecture and Design	The developer might choose a template engine that makes it easier for programmers to write vulnerable code.
Implementation	The programmer might not use engine's built-in sandboxes or other capabilities to escape or otherwise prevent template injection from untrusted input.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Python (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

Class: Interpreted (Undetermined Prevalence)

Operating Systems

Class: Not OS-Specific (Undetermined Prevalence)

Technologies

AI/ML (Undetermined Prevalence)

Class: Client Server (Undetermined Prevalence)

Observed Examples

Reference	Description
CVE-2024-34359	Chain: Python bindings for LLM library do not use a sandboxed environment when parsing a template and constructing a prompt, allowing jinja2 Server Side Template Injection and code execution - one variant of a "prompt injection" attack.
CVE-2017-16783	server-side template injection in content management server
CVE-2020-9437	authentication / identity management product has client-side template injection
CVE-2020-12790	Server-Side Template Injection using a Twig template
CVE-2021-21244	devops platform allows SSTI
CVE-2020-4027	bypass of Server-Side Template Injection protection mechanism with macros in Velocity templates
CVE-2020-26282	web browser proxy server allows Java EL expressions from Server-Side Template Injection
CVE-2020-1961	SSTI involving mail templates and JEXL expressions
CVE-2019-19999	product does not use a "safe" setting for a FreeMarker configuration, allowing SSTI
CVE-2018-20465	product allows read of sensitive database username/password variables using server-side template injection

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1409	Comprehensive Categorization: Injection

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Relationship

Since expression languages are often used in templating languages, there may be some overlap with CWE-917 (Expression Language Injection). XSS (CWE-79) is also co-located with template injection.

Maintenance

The interrelationships and differences between CWE-917 and CWE-1336 need to be further clarified.

References

[REF-1193] James Kettle. "Server-Side Template Injection". 2015-08-05. <https://portswigger.net/research/server-side-template-injection>. URL validated: 2023-04-07.

[REF-1194] James Kettle. "Server-Side Template Injection: RCE For The Modern Web App". 2015-12-27. <https://www.youtube.com/watch?v=3cT0uE7Y87s>.

Content History

Submissions
Submission Date	Submitter	Organization
2021-07-19 (CWE 4.5, 2021-07-20)	CWE Content Team	MITRE
2021-07-19 (CWE 4.5, 2021-07-20)
Modifications
Modification Date	Modifier	Organization
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Maintenance_Notes, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-07-16 (CWE 4.15, 2024-07-16)	CWE Content Team	MITRE
2024-07-16 (CWE 4.15, 2024-07-16)	updated Applicable_Platforms, Observed_Examples

Weakness ID: 917

View customized information:

Description

The product constructs all or part of an expression language (EL) statement in a framework such as a Java Server Page (JSP) using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended EL statement before it is executed.

Extended Description

Frameworks such as Java Server Page (JSP) allow a developer to insert executable expressions within otherwise-static content. When the developer is not aware of the executable nature of these expressions and/or does not disable them, then if an attacker can inject expressions, this could lead to code execution or other unexpected behaviors.

Alternate Terms

EL Injection

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data
Integrity	Technical Impact: Execute Unauthorized Code or Commands

Potential Mitigations

Phase: Architecture and Design

Avoid adding user-controlled data into an expression interpreter when possible.

Phase: Implementation

If user-controlled data must be added to an expression interpreter, one or more of the following should be performed:

Validate that the user input will not evaluate as an expression

Encode the user input in a way that ensures it is not evaluated as an expression

Phases: System Configuration; Operation

The framework or tooling might allow the developer to disable or deactivate the processing of EL expressions, such as setting the isELIgnored attribute for a JSP page to "true".

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	77	Improper Neutralization of Special Elements used in a Command ('Command Injection')
PeerOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1336	Improper Neutralization of Special Elements Used in a Template Engine

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	137	Data Neutralization Issues

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	74	Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	77	Improper Neutralization of Special Elements used in a Command ('Command Injection')

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	77	Improper Neutralization of Special Elements used in a Command ('Command Injection')

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Observed Examples

Reference	Description
CVE-2021-44228	Product does not neutralize ${xyz} style expressions, allowing remote code execution. (log4shell vulnerability in log4j)

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1027	OWASP Top Ten 2017 Category A1 - Injection
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1347	OWASP Top Ten 2021 Category A03:2021 - Injection
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1409	Comprehensive Categorization: Injection

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Relationship

In certain versions of Spring 3.0.5 and earlier, there was a vulnerability (CVE-2011-2730) in which Expression Language tags would be evaluated twice, which effectively exposed any application to EL injection. However, even for later versions, this weakness is still possible depending on configuration.

Maintenance

The interrelationships and differences between CWE-917 and CWE-1336 need to be further clarified.

References

[REF-911] Stefano Di Paola and Arshan Dabirsiaghi. "Expression Language Injection". 2011-09-12. <https://mindedsecurity.com/wp-content/uploads/2020/10/ExpressionLanguageInjection.pdf>. URL validated: 2023-04-07.

[REF-912] Dan Amodio. "Remote Code with Expression Language Injection". 2012-12-14. <http://danamodio.com/appsec/research/spring-remote-code-with-expression-language-injection/>. URL validated: 2023-04-07.

[REF-1279] CWE/CAPEC. "Neutralizing Your Inputs: A Log4Shell Weakness Story". <https://medium.com/@CWE_CAPEC/neutralizing-your-inputs-a-log4shell-weakness-story-89954c8b25c9>.

[REF-1280] OWASP. "Expression Language Injection". <https://owasp.org/www-community/vulnerabilities/Expression_Language_Injection>.

Content History

Submissions
Submission Date	Submitter	Organization
2013-02-15 (CWE 2.4, 2013-02-21)	CWE Content Team	MITRE
2013-02-15 (CWE 2.4, 2013-02-21)
Contributions
Contribution Date	Contributor	Organization
2013-02-15	Dan Amodio, Dave Wichers	Aspect Security
2013-02-15	Suggested adding this weakness and provided references.
Modifications
Modification Date	Modifier	Organization
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated References
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated References
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Description, Maintenance_Notes, Observed_Examples, Potential_Mitigations, References, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 1335

View customized information:

Description

An integer value is specified to be shifted by a negative amount or an amount greater than or equal to the number of bits contained in the value causing an unexpected or indeterminate result.

Extended Description

Specifying a value to be shifted by a negative amount is undefined in various languages. Various computer architectures implement this action in different ways. The compilers and interpreters when generating code to accomplish a shift generally do not do a check for this issue.

Specifying an over-shift, a shift greater than or equal to the number of bits contained in a value to be shifted, produces a result which varies by architecture and compiler. In some languages, this action is specifically listed as producing an undefined result.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: DoS: Crash, Exit, or Restart

Potential Mitigations

Phase: Implementation

Implicitly or explicitly add checks and mitigation for negative or over-shift values.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	682	Incorrect Calculation

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	189	Numeric Errors

Modes Of Introduction

Phase	Note
Implementation	Adding shifts without properly verifying the size and sign of the shift amount.

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

C# (Undetermined Prevalence)

Java (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

Operating Systems

Class: Not OS-Specific (Undetermined Prevalence)

Technologies

Class: Not Technology-Specific (Undetermined Prevalence)

Demonstrative Examples

Example 1

A negative shift amount for an x86 or x86_64 shift instruction will produce the number of bits to be shifted by taking a 2's-complement of the shift amount and effectively masking that amount to the lowest 6 bits for a 64 bit shift instruction.

(bad code)

Example Language: C

unsigned int r = 1 << -5;

The example above ends up with a shift amount of -5. The hexadecimal value is FFFFFFFFFFFFFFFD which, when bits above the 6th bit are masked off, the shift amount becomes a binary shift value of 111101 which is 61 decimal. A shift of 61 produces a very different result than -5. The previous example is a very simple version of the following code which is probably more realistic of what happens in a real system.

(bad code)

Example Language: C

int choose_bit(int reg_bit, int bit_number_from_elsewhere)
{

if (NEED_TO_SHIFT)
{

reg_bit -= bit_number_from_elsewhere;

}
return reg_bit;

}
unsigned int handle_io_register(unsigned int *r)
{

unsigned int the_bit = 1 << choose_bit(5, 10);
*r |= the_bit;
return the_bit;

}

(good code)

Example Language: C

int choose_bit(int reg_bit, int bit_number_from_elsewhere)
{

if (NEED_TO_SHIFT)
{

reg_bit -= bit_number_from_elsewhere;

}
return reg_bit;

}

unsigned int handle_io_register(unsigned int *r)
{

int the_bit_number = choose_bit(5, 10);
if ((the_bit_number > 0) && (the_bit_number < 63))
{

unsigned int the_bit = 1 << the_bit_number;
*r |= the_bit;

}
return the_bit;

}

Note that the good example not only checks for negative shifts and disallows them, but it also checks for over-shifts. No bit operation is done if the shift is out of bounds. Depending on the program, perhaps an error message should be logged.

Observed Examples

Reference	Description
CVE-2009-4307	An unexpected large value in the ext4 filesystem causes an overshift condition resulting in a divide by zero.
CVE-2012-2100	An unexpected large value in the ext4 filesystem causes an overshift condition resulting in a divide by zero - fix of CVE-2009-4307.
CVE-2020-8835	An overshift in a kernel allowed out of bounds reads and writes resulting in a root takeover.
CVE-2015-1607	Program is not properly handling signed bitwise left-shifts causing an overlapping memcpy memory range error.
CVE-2016-9842	Compression function improperly executes a signed left shift of a negative integer.
CVE-2018-18445	Some kernels improperly handle right shifts of 32 bit numbers in a 64 bit register.
CVE-2013-4206	Putty has an incorrectly sized shift value resulting in an overshift.
CVE-2018-20788	LED driver overshifts under certain conditions resulting in a DoS.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1408	Comprehensive Categorization: Incorrect Calculation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Content History

Submissions
Submission Date	Submitter	Organization
2021-03-29 (CWE 4.5, 2021-07-20)	CWE Content Team	MITRE
2021-03-29 (CWE 4.5, 2021-07-20)
Modifications
Modification Date	Modifier	Organization
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Demonstrative_Examples, Observed_Examples
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 1235

View customized information:

Description

The code uses boxed primitives, which may introduce inefficiencies into performance-critical operations.

Extended Description

Languages such as Java and C# support automatic conversion through their respective compilers from primitive types into objects of the corresponding wrapper classes, and vice versa. For example, a compiler might convert an int to Integer (called autoboxing) or an Integer to int (called unboxing). This eliminates forcing the programmer to perform these conversions manually, which makes the code cleaner.

However, this feature comes at a cost of performance and can lead to resource exhaustion and impact availability when used with generic collections. Therefore, they should not be used for scientific computing or other performance critical operations. They are only suited to support "impedance mismatch" between reference types and primitives.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other); Reduce Performance Incorrect autoboxing/unboxing would result in reduced performance, which sometimes can lead to resource consumption issues.	Low

Potential Mitigations

Phase: Implementation

Use of boxed primitives should be limited to certain situations such as when calling methods with typed parameters. Examine the use of boxed primitives prior to use. Use SparseArrays or ArrayMap instead of HashMap to avoid performance overhead.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	400	Uncontrolled Resource Consumption

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1006	Bad Coding Practices

Modes Of Introduction

Phase	Note
Implementation	The programmer may use boxed primitives when not strictly necessary.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Operating Systems

Class: Not OS-Specific (Undetermined Prevalence)

Architectures

Class: Not Architecture-Specific (Undetermined Prevalence)

Technologies

Class: Not Technology-Specific (Undetermined Prevalence)

Demonstrative Examples

Example 1

Java has a boxed primitive for each primitive type. A long can be represented with the boxed primitive Long. Issues arise where boxed primitives are used when not strictly necessary.

(bad code)

Example Language: Java

Long count = 0L;
for (long i = 0; i < Integer.MAX_VALUE; i++) {

count += i;

}

In the above loop, we see that the count variable is declared as a boxed primitive. This causes autoboxing on the line that increments. This causes execution to be magnitudes less performant (time and possibly space) than if the "long" primitive was used to declare the count variable, which can impact availability of a resource.

Example 2

This code uses primitive long which fixes the issue.

(good code)

Example Language: Java

long count = 0L;
for (long i = 0; i < Integer.MAX_VALUE; i++) {

count += i;

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
SEI CERT Oracle Coding Standard for Java	EXP04-J		Do not pass arguments to certain Java Collections Framework methods that are a different type than the collection parameter type
ISA/IEC 62443	Part 4-1		Req SI-2

References

[REF-1051] "Oracle Java Documentation". <https://docs.oracle.com/javase/1.5.0/docs/guide/language/autoboxing.html>.

[REF-1052] The Software Engineering Institute. "SEI CERT Oracle Coding Standard for Java : Rule 02. Expressions (EXP)". <https://wiki.sei.cmu.edu/confluence/display/java/EXP04-J.+Do+not+pass+arguments+to+certain+Java+Collections+Framework+methods+that+are+a+different+type+than+the+collection+parameter+type>.

Content History

Submissions
Submission Date	Submitter	Organization
2019-10-14 (CWE 4.0, 2020-02-24)	Joe Harvey
2019-10-14 (CWE 4.0, 2020-02-24)
Contributions
Contribution Date	Contributor	Organization
2023-04-25	"Mapping CWE to 62443" Sub-Working Group	CWE-CAPEC ICS/OT SIG
2023-04-25	Suggested mappings to ISA/IEC 62443.
Modifications
Modification Date	Modifier	Organization
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Taxonomy_Mappings
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 192

View customized information:

Description

Integer coercion refers to a set of flaws pertaining to the type casting, extension, or truncation of primitive data types.

Extended Description

Several flaws fall under the category of integer coercion errors. For the most part, these errors in and of themselves result only in availability and data integrity issues. However, in some circumstances, they may result in other, more complicated security related flaws, such as buffer overflow conditions.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Crash, Exit, or Restart Integer coercion often leads to undefined states of execution resulting in infinite loops or crashes.
Integrity Confidentiality Availability	Technical Impact: Execute Unauthorized Code or Commands In some cases, integer coercion errors can lead to exploitable buffer overflow conditions, resulting in the execution of arbitrary code.
Integrity Other	Technical Impact: Other Integer coercion errors result in an incorrect value being stored for the variable in question.

Potential Mitigations

Phase: Requirements

A language which throws exceptions on ambiguous data casts might be chosen.

Phase: Architecture and Design

Design objects and program flow such that multiple or complex casts are unnecessary

Phase: Implementation

Ensure that any data type casting that you must used is entirely understood in order to reduce the plausibility of error in use.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	681	Incorrect Conversion between Numeric Types

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following code is intended to read an incoming packet from a socket and extract one or more headers.

(bad code)

Example Language: C

DataPacket *packet;
int numHeaders;
PacketHeader *headers;

sock=AcceptSocketConnection();
ReadPacket(packet, sock);
numHeaders =packet->headers;

if (numHeaders > 100) {

ExitError("too many headers!");

}
headers = malloc(numHeaders * sizeof(PacketHeader);
ParsePacketHeaders(packet, headers);

The code performs a check to make sure that the packet does not contain too many headers. However, numHeaders is defined as a signed int, so it could be negative. If the incoming packet specifies a value such as -3, then the malloc calculation will generate a negative number (say, -300 if each header can be a maximum of 100 bytes). When this result is provided to malloc(), it is first converted to a size_t type. This conversion then produces a large value such as 4294966996, which may cause malloc() to fail or to allocate an extremely large amount of memory (CWE-195). With the appropriate negative numbers, an attacker could trick malloc() into using a very small positive number, which then allocates a buffer that is much smaller than expected, potentially leading to a buffer overflow.

Example 2

The following code reads a maximum size and performs validation on that size. It then performs a strncpy, assuming it will not exceed the boundaries of the array. While the use of "short s" is forced in this particular example, short int's are frequently used within real-world code, such as code that processes structured data.

(bad code)

Example Language: C

int GetUntrustedInt () {

return(0x0000FFFF);

}

void main (int argc, char **argv) {

char path[256];
char *input;
int i;
short s;
unsigned int sz;

i = GetUntrustedInt();
s = i;
/* s is -1 so it passes the safety check - CWE-697 */
if (s > 256) {

DiePainfully("go away!\n");

}

/* s is sign-extended and saved in sz */
sz = s;

/* output: i=65535, s=-1, sz=4294967295 - your mileage may vary */
printf("i=%d, s=%d, sz=%u\n", i, s, sz);

input = GetUserInput("Enter pathname:");

/* strncpy interprets s as unsigned int, so it's treated as MAX_INT
(CWE-195), enabling buffer overflow (CWE-119) */
strncpy(path, input, s);
path[255] = '\0'; /* don't want CWE-170 */
printf("Path is: %s\n", path);

}

This code first exhibits an example of CWE-839, allowing "s" to be a negative number. When the negative short "s" is converted to an unsigned integer, it becomes an extremely large positive integer. When this converted integer is used by strncpy() it will lead to a buffer overflow (CWE-119).

Observed Examples

Reference	Description
CVE-2022-2639	Chain: integer coercion error (CWE-192) prevents a return value from indicating an error, leading to out-of-bounds write (CWE-787)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	738	CERT C Secure Coding Standard (2008) Chapter 5 - Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	872	CERT C++ Secure Coding Section 04 - Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1158	SEI CERT C Coding Standard - Guidelines 04. Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Maintenance

Within C, it might be that "coercion" is semantically different than "casting", possibly depending on whether the programmer directly specifies the conversion, or if the compiler does it implicitly. This has implications for the presentation of this entry and others, such as CWE-681, and whether there is enough of a difference for these entries to be split.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Integer coercion error
CERT C Secure Coding	INT02-C		Understand integer conversion rules
CERT C Secure Coding	INT05-C		Do not use input functions to convert character data if they cannot handle all possible inputs
CERT C Secure Coding	INT31-C	Exact	Ensure that integer conversions do not result in lost or misinterpreted data

References

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 7: Integer Overflows." Page 119. McGraw-Hill. 2010.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 6, "Sign Extension", Page 248. 1st Edition. Addison Wesley. 2006.

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Maintenance_Notes, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Description, Other_Notes
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, References
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, Taxonomy_Mappings, Type
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples, Maintenance_Notes, References
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples

Weakness ID: 191

View customized information:

Description

The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

Extended Description

This can happen in signed and unsigned cases.

Alternate Terms

Integer underflow:

"Integer underflow" is sometimes used to identify signedness errors in which an originally positive number becomes negative as a result of subtraction. However, there are cases of bad subtraction in which unsigned integers are involved, so it's not always a signedness issue.

"Integer underflow" is occasionally used to describe array index errors in which the index is negative.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Instability This weakness will generally lead to undefined behavior and therefore crashes. In the case of overflows involving loop index variables, the likelihood of infinite loops is also high.
Integrity	Technical Impact: Modify Memory If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.
Confidentiality Availability Access Control	Technical Impact: Execute Unauthorized Code or Commands; Bypass Protection Mechanism This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	682	Incorrect Calculation

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	189	Numeric Errors

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	682	Incorrect Calculation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following example subtracts from a 32 bit signed integer.

(bad code)

Example Language: C

#include <stdio.h>
#include <stdbool.h>
main (void)
{

int i;
i = -2147483648;
i = i - 1;
return 0;

}

The example has an integer underflow. The value of i is already at the lowest negative value possible, so after subtracting 1, the new value of i is 2147483647.

Example 2

This code performs a stack allocation based on a length calculation.

(bad code)

Example Language: C

int a = 5, b = 6;
size_t len = a - b;
char buf[len]; // Just blows up the stack

}

Since a and b are declared as signed ints, the "a - b" subtraction gives a negative result (-1). However, since len is declared to be unsigned, len is cast to an extremely large positive number (on 32-bit systems - 4294967295). As a result, the buffer buf[len] declaration uses an extremely large size to allocate on the stack, very likely more than the entire computer's memory space.

Miscalculations usually will not be so obvious. The calculation will either be complicated or the result of an attacker's input to attain the negative value.

Observed Examples

Reference	Description
CVE-2004-0816	Integer underflow in firewall via malformed packet.
CVE-2004-1002	Integer underflow by packet with invalid length.
CVE-2005-0199	Long input causes incorrect length calculation.
CVE-2005-1891	Malformed icon causes integer underflow in loop counter variable.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1137	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 03. Numeric Types and Operations (NUM)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1158	SEI CERT C Coding Standard - Guidelines 04. Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1408	Comprehensive Categorization: Incorrect Calculation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Integer underflow (wrap or wraparound)
Software Fault Patterns	SFP1		Glitch in computation
CERT C Secure Coding	INT30-C	Imprecise	Ensure that unsigned integer operations do not wrap
CERT C Secure Coding	INT32-C	Imprecise	Ensure that operations on signed integers do not result in overflow

References

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 7: Integer Overflows." Page 119. McGraw-Hill. 2010.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	PLOVER
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Demonstrative_Example
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Alternate_Terms, Applicable_Platforms, Relationships, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, References, Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Research_Gaps
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 245

View customized information:

Description

The J2EE application directly manages connections, instead of using the container's connection management facilities.

Extended Description

The J2EE standard forbids the direct management of connections. It requires that applications use the container's resource management facilities to obtain connections to resources. Every major web application container provides pooled database connection management as part of its resource management framework. Duplicating this functionality in an application is difficult and error prone, which is part of the reason it is forbidden under the J2EE standard.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following example, the class DatabaseConnection opens and manages a connection to a database for a J2EE application. The method openDatabaseConnection opens a connection to the database using a DriverManager to create the Connection object conn to the database specified in the string constant CONNECT_STRING.

(bad code)

Example Language: Java

public class DatabaseConnection {

private static final String CONNECT_STRING = "jdbc:mysql://localhost:3306/mysqldb";
private Connection conn = null;

public DatabaseConnection() {
}

public void openDatabaseConnection() {

try {

conn = DriverManager.getConnection(CONNECT_STRING);

} catch (SQLException ex) {...}

}

// Member functions for retrieving database connection and accessing database
...

}

The use of the DriverManager class to directly manage the connection to the database violates the J2EE restriction against the direct management of connections. The J2EE application should use the web application container's resource management facilities to obtain a connection to the database as shown in the following example.

(good code)

public class DatabaseConnection {

private static final String DB_DATASRC_REF = "jdbc:mysql://localhost:3306/mysqldb";
private Connection conn = null;

public DatabaseConnection() {
}

public void openDatabaseConnection() {

try {

InitialContext ctx = new InitialContext();
DataSource datasource = (DataSource) ctx.lookup(DB_DATASRC_REF);
conn = datasource.getConnection();

} catch (NamingException ex) {...}
} catch (SQLException ex) {...}

}

// Member functions for retrieving database connection and accessing database
...

}

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	227	7PK - API Abuse
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Bad Practices: getConnection()
Software Fault Patterns	SFP3		Use of an improper API

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	J2EE Bad Practices: getConnection()

Weakness ID: 246

View customized information:

Description

The J2EE application directly uses sockets instead of using framework method calls.

Extended Description

The J2EE standard permits the use of sockets only for the purpose of communication with legacy systems when no higher-level protocol is available. Authoring your own communication protocol requires wrestling with difficult security issues.

Without significant scrutiny by a security expert, chances are good that a custom communication protocol will suffer from security problems. Many of the same issues apply to a custom implementation of a standard protocol. While there are usually more resources available that address security concerns related to implementing a standard protocol, these resources are also available to attackers.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Architecture and Design

Use framework method calls instead of using sockets directly.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following example opens a socket to connect to a remote server.

(bad code)

Example Language: Java

public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

// Perform servlet tasks.
...

// Open a socket to a remote server (bad).
Socket sock = null;

try {

sock = new Socket(remoteHostname, 3000);

// Do something with the socket.
...

} catch (Exception e) {

...

}

A Socket object is created directly within the Java servlet, which is a dangerous way to manage remote connections.

Weakness Ordinalities

Ordinality	Description
Resultant	(where the weakness is typically related to the presence of some other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	227	7PK - API Abuse
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Bad Practices: Sockets
Software Fault Patterns	SFP3		Use of an improper API

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	J2EE Bad Practices: Sockets

Weakness ID: 383

View customized information:

Description

Thread management in a Web application is forbidden in some circumstances and is always highly error prone.

Extended Description

Thread management in a web application is forbidden by the J2EE standard in some circumstances and is always highly error prone. Managing threads is difficult and is likely to interfere in unpredictable ways with the behavior of the application container. Even without interfering with the container, thread management usually leads to bugs that are hard to detect and diagnose like deadlock, race conditions, and other synchronization errors.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Architecture and Design

For EJB, use framework approaches for parallel execution, instead of using threads.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	695	Use of Low-Level Functionality

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following example, a new Thread object is created and invoked directly from within the body of a doGet() method in a Java servlet.

(bad code)

Example Language: Java

public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

// Perform servlet tasks.
...

// Create a new thread to handle background processing.
Runnable r = new Runnable() {

public void run() {

// Process and store request statistics.
...

}

};

new Thread(r).start();

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Affected Resources

System Process

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	361	7PK - Time and State
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Bad Practices: Threads
Software Fault Patterns	SFP3		Use of an improper API

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Description, Other_Notes, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-01-30	J2EE Bad Practices: Threads

2008-04-11	J2EE Bad Practices: Use of Threads

Weakness ID: 579

View customized information:

Description

The product stores a non-serializable object as an HttpSession attribute, which can hurt reliability.

Extended Description

A J2EE application can make use of multiple JVMs in order to improve application reliability and performance. In order to make the multiple JVMs appear as a single application to the end user, the J2EE container can replicate an HttpSession object across multiple JVMs so that if one JVM becomes unavailable another can step in and take its place without disrupting the flow of the application. This is only possible if all session data is serializable, allowing the session to be duplicated between the JVMs.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Implementation

In order for session replication to work, the values the product stores as attributes in the session must implement the Serializable interface.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1018	Manage User Sessions

Modes Of Introduction

Phase	Note
Implementation	REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following class adds itself to the session, but because it is not serializable, the session can no longer be replicated.

(bad code)

Example Language: Java

public class DataGlob {

String globName;
String globValue;

public void addToSession(HttpSession session) {

session.setAttribute("glob", this);

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1348	OWASP Top Ten 2021 Category A04:2021 - Insecure Design
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP1		Glitch in computation

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Modes_of_Introduction, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description, Potential_Mitigations
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 382

View customized information:

Description

A J2EE application uses System.exit(), which also shuts down its container.

Extended Description

It is never a good idea for a web application to attempt to shut down the application container. Access to a function that can shut down the application is an avenue for Denial of Service (DoS) attacks.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Crash, Exit, or Restart

Potential Mitigations

Phase: Architecture and Design

Strategy: Separation of Privilege

The shutdown function should be a privileged function available only to a properly authorized administrative user

Phase: Implementation

Web applications should not call methods that cause the virtual machine to exit, such as System.exit()

Phase: Implementation

Web applications should also not throw any Throwables to the application server as this may adversely affect the container.

Phase: Implementation

Non-web applications may have a main() method that contains a System.exit(), but generally should not call System.exit() from other locations in the code

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	705	Incorrect Control Flow Scoping

Modes Of Introduction

Phase	Note
Implementation	A call to System.exit() is probably part of leftover debug code or code imported from a non-J2EE application.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

Included in the doPost() method defined below is a call to System.exit() in the event of a specific exception.

(bad code)

Example Language: Java

Public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

try {

...

} catch (ApplicationSpecificException ase) {

logger.error("Caught: " + ase.toString());
System.exit(1);

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	361	7PK - Time and State
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	730	OWASP Top Ten 2004 Category A9 - Denial of Service
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1001	SFP Secondary Cluster: Use of an Improper API
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1141	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 07. Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Bad Practices: System.exit()
OWASP Top Ten 2004	A9	CWE More Specific	Denial of Service
The CERT Oracle Secure Coding Standard for Java (2011)	ERR09-J		Do not allow untrusted code to terminate the JVM
Software Fault Patterns	SFP3		Use of an improper API

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Modes_of_Introduction, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	J2EE Bad Practices: System.exit()

Weakness ID: 594

View customized information:

Description

When the J2EE container attempts to write unserializable objects to disk there is no guarantee that the process will complete successfully.

Extended Description

In heavy load conditions, most J2EE application frameworks flush objects to disk to manage memory requirements of incoming requests. For example, session scoped objects, and even application scoped objects, are written to disk when required. While these application frameworks do the real work of writing objects to disk, they do not enforce that those objects be serializable, thus leaving the web application vulnerable to crashes induced by serialization failure. An attacker may be able to mount a denial of service attack by sending enough requests to the server to force the web application to save objects to disk.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data Data represented by unserializable objects can be corrupted.
Availability	Technical Impact: DoS: Crash, Exit, or Restart Non-serializability of objects can lead to system crash.

Potential Mitigations

Phases: Architecture and Design; Implementation

All objects that become part of session and application scope must implement the java.io.Serializable interface to ensure serializability of containing objects.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1076	Insufficient Adherence to Expected Conventions

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example, a Customer Entity JavaBean provides access to customer information in a database for a business application. The Customer Entity JavaBean is used as a session scoped object to return customer information to a Session EJB.

(bad code)

Example Language: Java

@Entity
public class Customer {

private String id;
private String firstName;
private String lastName;
private Address address;

public Customer() {
}

public Customer(String id, String firstName, String lastName) {...}

@Id
public String getCustomerId() {...}

public void setCustomerId(String id) {...}

public String getFirstName() {...}

public void setFirstName(String firstName) {...}

public String getLastName() {...}

public void setLastName(String lastName) {...}

@OneToOne()
public Address getAddress() {...}

public void setAddress(Address address) {...}

}

However, the Customer Entity JavaBean is an unserialized object which can cause serialization failure and crash the application when the J2EE container attempts to write the object to the system. Session scoped objects must implement the Serializable interface to ensure that the objects serialize properly.

(good code)

Example Language: Java

public class Customer implements Serializable {...}

Weakness Ordinalities

Ordinality	Description
Indirect	(where the weakness is a quality issue that might indirectly make it easier to introduce security-relevant weaknesses or make them more difficult to detect)
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP1		Glitch in computation

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Relationships, Other_Notes
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Weakness_Ordinalities
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Relationships
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Persistence in J2EE Frameworks

Weakness ID: 5

View customized information:

Description

Information sent over a network can be compromised while in transit. An attacker may be able to read or modify the contents if the data are sent in plaintext or are weakly encrypted.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data
Integrity	Technical Impact: Modify Application Data

Potential Mitigations

Phase: System Configuration

The product configuration should ensure that SSL or an encryption mechanism of equivalent strength and vetted reputation is used for all access-controlled pages.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	319	Cleartext Transmission of Sensitive Information

Modes Of Introduction

Phase	Note
Implementation
Operation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	2	7PK - Environment
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	731	OWASP Top Ten 2004 Category A10 - Insecure Configuration Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1402	Comprehensive Categorization: Encryption

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Other

If an application uses SSL to guarantee confidential communication with client browsers, the application configuration should make it impossible to view any access controlled page without SSL. There are three common ways for SSL to be bypassed:

A user manually enters URL and types "HTTP" rather than "HTTPS".
Attackers intentionally send a user to an insecure URL.
A programmer erroneously creates a relative link to a page in the application, which does not switch from HTTP to HTTPS. (This is particularly easy to do when the link moves between public and secured areas on a web site.)

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Misconfiguration: Insecure Transport

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Common_Consequences, Description
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Potential_Mitigations
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	J2EE Misconfiguration: Insecure Transport

Weakness ID: 6

View customized information:

Description

The J2EE application is configured to use an insufficient session ID length.

Extended Description

If an attacker can guess or steal a session ID, then they may be able to take over the user's session (called session hijacking). The number of possible session IDs increases with increased session ID length, making it more difficult to guess or steal a session ID.

Common Consequences

Scope	Impact	Likelihood
Access Control	Technical Impact: Gain Privileges or Assume Identity If an attacker can guess an authenticated user's session identifier, they can take over the user's session.

Potential Mitigations

Phase: Implementation

Session identifiers should be at least 128 bits long to prevent brute-force session guessing. A shorter session identifier leaves the application open to brute-force session guessing attacks.

Phase: Implementation

A lower bound on the number of valid session identifiers that are available to be guessed is the number of users that are active on a site at any given moment. However, any users that abandon their sessions without logging out will increase this number. (This is one of many good reasons to have a short inactive session timeout.) With a 64 bit session identifier, assume 32 bits of entropy. For a large web site, assume that the attacker can try 1,000 guesses per second and that there are 10,000 valid session identifiers at any given moment. Given these assumptions, the expected time for an attacker to successfully guess a valid session identifier is less than 4 minutes. Now assume a 128 bit session identifier that provides 64 bits of entropy. With a very large web site, an attacker might try 10,000 guesses per second with 100,000 valid session identifiers available to be guessed. Given these assumptions, the expected time for an attacker to successfully guess a valid session identifier is greater than 292 years.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	334	Small Space of Random Values

Relevant to the view "Architectural Concepts" (CWE-1008)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1018	Manage User Sessions

Background Details

Session ID's can be used to identify communicating parties in a web environment.

The expected number of seconds required to guess a valid session identifier is given by the equation: (2^B+1)/(2*A*S) Where: - B is the number of bits of entropy in the session identifier. - A is the number of guesses an attacker can try each second. - S is the number of valid session identifiers that are valid and available to be guessed at any given time. The number of bits of entropy in the session identifier is always less than the total number of bits in the session identifier. For example, if session identifiers were provided in ascending order, there would be close to zero bits of entropy in the session identifier no matter the identifier's length. Assuming that the session identifiers are being generated using a good source of random numbers, we will estimate the number of bits of entropy in a session identifier to be half the total number of bits in the session identifier. For realistic identifier lengths this is possible, though perhaps optimistic.

Modes Of Introduction

Phase	Note
Architecture and Design	COMMISSION: This weakness refers to an incorrect design related to an architectural security tactic.
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following XML example code is a deployment descriptor for a Java web application deployed on a Sun Java Application Server. This deployment descriptor includes a session configuration property for configuring the session ID length.

(bad code)

Example Language: XML

<sun-web-app>

...
<session-config>

<session-properties>

<description>The number of bytes in this web module's session ID.</description>

</property>

</session-properties>

</session-config>
...

</sun-web-app>

This deployment descriptor has set the session ID length for this Java web application to 8 bytes (or 64 bits). The session ID length for Java web applications should be set to 16 bytes (128 bits) to prevent attackers from guessing and/or stealing a session ID and taking over a user's session.

Note for most application servers including the Sun Java Application Server the session ID length is by default set to 128 bits and should not be changed. And for many application servers the session ID length cannot be changed from this default setting. Check your application server documentation for the session ID length default setting and configuration options to ensure that the session ID length is set to 128 bits.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	2	7PK - Environment
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	731	OWASP Top Ten 2004 Category A10 - Insecure Configuration Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	965	SFP Secondary Cluster: Insecure Session Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1414	Comprehensive Categorization: Randomness

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Misconfiguration: Insufficient Session-ID Length

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-21	Exploitation of Trusted Identifiers
CAPEC-59	Session Credential Falsification through Prediction

References

[REF-482] Zvi Gutterman. "Hold Your Sessions: An Attack on Java Session-id Generation". 2005-02-13. <https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/gm05.pdf>. URL validated: 2023-04-07.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Background_Details, Description
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Description, Other_Notes, References
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Background_Details, Common_Consequences, Enabling_Factors_for_Exploitation, Other_Notes, Potential_Mitigations
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Description, Enabling_Factors_for_Exploitation, Modes_of_Introduction, References, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 7

View customized information:

Description

The default error page of a web application should not display sensitive information about the product.

Extended Description

A Web application must define a default error page for 4xx errors (e.g. 404), 5xx (e.g. 500) errors and catch java.lang.Throwable exceptions to prevent attackers from mining information from the application container's built-in error response.

When an attacker explores a web site looking for vulnerabilities, the amount of information that the site provides is crucial to the eventual success or failure of any attempted attacks.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data A stack trace might show the attacker a malformed SQL query string, the type of database being used, and the version of the application container. This information enables the attacker to target known vulnerabilities in these components.

Potential Mitigations

Phase: Implementation

Handle exceptions appropriately in source code.

Phases: Implementation; System Configuration

Always define appropriate error pages. The application configuration should specify a default error page in order to guarantee that the application will never leak error messages to an attacker. Handling standard HTTP error codes is useful and user-friendly in addition to being a good security practice, and a good configuration will also define a last-chance error handler that catches any exception that could possibly be thrown by the application.

Phase: Implementation

Do not attempt to process an error or attempt to mask it.

Phase: Implementation

Verify return values are correct and do not supply sensitive information about the system.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	756	Missing Custom Error Page

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the snippet below, an unchecked runtime exception thrown from within the try block may cause the container to display its default error page (which may contain a full stack trace, among other things).

(bad code)

Example Language: Java

Public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

try {

...

} catch (ApplicationSpecificException ase) {

logger.error("Caught: " + ase.toString());

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	2	7PK - Environment
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	728	OWASP Top Ten 2004 Category A7 - Improper Error Handling
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	731	OWASP Top Ten 2004 Category A10 - Insecure Configuration Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1405	Comprehensive Categorization: Improper Check or Handling of Exceptional Conditions

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			J2EE Misconfiguration: Missing Error Handling

References

[REF-65] M. Howard, D. LeBlanc and J. Viega. "19 Deadly Sins of Software Security". McGraw-Hill/Osborne. 2005-07-26.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Name, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Common_Consequences, Description, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated References
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2009-03-10	J2EE Misconfiguration: Missing Error Handling

Weakness ID: 537

View customized information:

Description

In many cases, an attacker can leverage the conditions that cause unhandled exception errors in order to gain unauthorized access to the system.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data

Potential Mitigations

Phase: Implementation

Do not expose sensitive error information to the user.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	211	Externally-Generated Error Message Containing Sensitive Information

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example the class InputFileRead enables an input file to be read using a FileReader object. In the constructor of this class a default input file path is set to some directory on the local file system and the method setInputFile must be called to set the name of the input file to be read in the default directory. The method readInputFile will create the FileReader object and will read the contents of the file. If the method setInputFile is not called prior to calling the method readInputFile then the File object will remain null when initializing the FileReader object. A Java RuntimeException will be raised, and an error message will be output to the user.

(bad code)

Example Language: Java

public class InputFileRead {

private File readFile = null;
private FileReader reader = null;
private String inputFilePath = null;
private final String DEFAULT_FILE_PATH = "c:\\somedirectory\\";

public InputFileRead() {

inputFilePath = DEFAULT_FILE_PATH;

}

public void setInputFile(String inputFile) {

/* Assume appropriate validation / encoding is used and privileges / permissions are preserved */

}

public void readInputFile() {

try {

reader = new FileReader(readFile);
...

} catch (RuntimeException rex) {

System.err.println("Error: Cannot open input file in the directory " + inputFilePath);
System.err.println("Input file has not been set, call setInputFile method before calling readInputFile");

} catch (FileNotFoundException ex) {...}

}

However, the error message output to the user contains information regarding the default directory on the local file system. This information can be exploited and may lead to unauthorized access or use of the system. Any Java RuntimeExceptions that are handled should not expose sensitive information to the user.

Example 2

In the example below, the BankManagerLoginServlet servlet class will process a login request to determine if a user is authorized to use the BankManager Web service. The doPost method will retrieve the username and password from the servlet request and will determine if the user is authorized. If the user is authorized the servlet will go to the successful login page. Otherwise, the servlet will raise a FailedLoginException and output the failed login message to the error page of the service.

(bad code)

Example Language: Java

public class BankManagerLoginServlet extends HttpServlet {

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

try {

// Get username and password from login page request
String username = request.getParameter("username");
String password = request.getParameter("password");
// Authenticate user
BankManager bankMgr = new BankManager();
boolean isAuthentic = bankMgr.authenticateUser(username, password);
// If user is authenticated then go to successful login page
if (isAuthentic) {

request.setAttribute("login", new String("Login Successful."));
getServletContext().getRequestDispatcher("/BankManagerServiceLoggedIn.jsp"). forward(request, response);

}
else {

// Otherwise, raise failed login exception and output unsuccessful login message to error page
throw new FailedLoginException("Failed Login for user " + username + " with password " + password);

}

} catch (FailedLoginException ex) {

// output failed login message to error page
request.setAttribute("error", new String("Login Error"));
request.setAttribute("message", ex.getMessage());
getServletContext().getRequestDispatcher("/ErrorPage.jsp").forward(request, response);

}

However, the output message generated by the FailedLoginException includes the user-supplied password. Even if the password is erroneous, it is probably close to the correct password. Since it is printed to the user's page, anybody who can see the screen display will be able to see the password. Also, if the page is cached, the password might be written to disk.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1349	OWASP Top Ten 2021 Category A05:2021 - Security Misconfiguration
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1417	Comprehensive Categorization: Sensitive Information Exposure

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	Anonymous Tool Vendor (under NDA)
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Taxonomy_Mappings
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Demonstrative_Examples, Potential_Mitigations
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples, Name
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Name, Relationships
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2011-03-29	Information Leak Through Java Runtime Error Message

2020-02-24	Information Exposure Through Java Runtime Error Message

Weakness ID: 478

View customized information:

Description

The code does not have a default case in an expression with multiple conditions, such as a switch statement.

Extended Description

If a multiple-condition expression (such as a switch in C) omits the default case but does not consider or handle all possible values that could occur, then this might lead to complex logical errors and resultant weaknesses. Because of this, further decisions are made based on poor information, and cascading failure results. This cascading failure may result in any number of security issues, and constitutes a significant failure in the system.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Varies by Context; Alter Execution Logic Depending on the logical circumstances involved, any consequences may result: e.g., issues of confidentiality, authentication, authorization, availability, integrity, accountability, or non-repudiation.

Potential Mitigations

Phase: Implementation

Ensure that there are no cases unaccounted for when adjusting program flow or values based on the value of a given variable. In the case of switch style statements, the very simple act of creating a default case can, if done correctly, mitigate this situation. Often however, the default case is used simply to represent an assumed option, as opposed to working as a check for invalid input. This is poor practice and in some cases is as bad as omitting a default case entirely.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1023	Incomplete Comparison with Missing Factors

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1006	Bad Coding Practices

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Python (Undetermined Prevalence)

JavaScript (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following does not properly check the return code in the case where the security_check function returns a -1 value when an error occurs. If an attacker can supply data that will invoke an error, the attacker can bypass the security check:

(bad code)

Example Language: C

#define FAILED 0
#define PASSED 1
int result;
...
result = security_check(data);
switch (result) {

case FAILED:

printf("Security check failed!\n");
exit(-1);
//Break never reached because of exit()
break;

case PASSED:

printf("Security check passed.\n");
break;

}
// program execution continues...
...

Instead a default label should be used for unaccounted conditions:

(good code)

Example Language: C

#define FAILED 0
#define PASSED 1
int result;
...
result = security_check(data);
switch (result) {

case FAILED:

printf("Security check failed!\n");
exit(-1);
//Break never reached because of exit()
break;

case PASSED:

printf("Security check passed.\n");
break;

default:

printf("Unknown error (%d), exiting...\n",result);
exit(-1);

}

This label is used because the assumption cannot be made that all possible cases are accounted for. A good practice is to reserve the default case for error handling.

Example 2

In the following Java example the method getInterestRate retrieves the interest rate for the number of points for a mortgage. The number of points is provided within the input parameter and a switch statement will set the interest rate value to be returned based on the number of points.

(bad code)

Example Language: Java

public static final String INTEREST_RATE_AT_ZERO_POINTS = "5.00";
public static final String INTEREST_RATE_AT_ONE_POINTS = "4.75";
public static final String INTEREST_RATE_AT_TWO_POINTS = "4.50";
...
public BigDecimal getInterestRate(int points) {

BigDecimal result = new BigDecimal(INTEREST_RATE_AT_ZERO_POINTS);

switch (points) {

case 0:

result = new BigDecimal(INTEREST_RATE_AT_ZERO_POINTS);
break;

case 1:

result = new BigDecimal(INTEREST_RATE_AT_ONE_POINTS);
break;

case 2:

result = new BigDecimal(INTEREST_RATE_AT_TWO_POINTS);
break;

}
return result;

}

However, this code assumes that the value of the points input parameter will always be 0, 1 or 2 and does not check for other incorrect values passed to the method. This can be easily accomplished by providing a default label in the switch statement that outputs an error message indicating an invalid value for the points input parameter and returning a null value.

(good code)

Example Language: Java

BigDecimal result = new BigDecimal(INTEREST_RATE_AT_ZERO_POINTS);

switch (points) {

case 0:

result = new BigDecimal(INTEREST_RATE_AT_ZERO_POINTS);
break;

case 1:

result = new BigDecimal(INTEREST_RATE_AT_ONE_POINTS);
break;

case 2:

result = new BigDecimal(INTEREST_RATE_AT_TWO_POINTS);
break;

default:

System.err.println("Invalid value for points, must be 0, 1 or 2");
System.err.println("Returning null value for interest rate");
result = null;

}

return result;

}

Example 3

In the following Python example the match-case statements (available in Python version 3.10 and later) perform actions based on the result of the process_data() function. The expected return is either 0 or 1. However, if an unexpected result (e.g., -1 or 2) is obtained then no actions will be taken potentially leading to an unexpected program state.

(bad code)

Example Language: Python

result = process_data(data)
match result:

case 0:

print("Properly handle zero case.")

case 1:

print("Properly handle one case.")

# program execution continues...

The recommended approach is to add a default case that captures any unexpected result conditions, regardless of how improbable these unexpected conditions might be, and properly handles them.

(good code)

Example Language: Python

result = process_data(data)
match result:

case 0:

print("Properly handle zero case.")

case 1:

print("Properly handle one case.")

case _:

print("Properly handle unexpected condition.")

# program execution continues...

Example 4

In the following JavaScript example the switch-case statements (available in JavaScript version 1.2 and later) are used to process a given step based on the result of a calcuation involving two inputs. The expected return is either 1, 2, or 3. However, if an unexpected result (e.g., 4) is obtained then no action will be taken potentially leading to an unexpected program state.

(bad code)

Example Language: JavaScript

let step = input1 + input2;
switch(step) {

case 1:

alert("Process step 1.");
break;

case 2:

alert("Process step 2.");
break;

case 3:

alert("Process step 3.");
break;

}
// program execution continues...

The recommended approach is to add a default case that captures any unexpected result conditions and properly handles them.

(good code)

Example Language: JavaScript

let step = input1 + input2;
switch(step) {

case 1:

alert("Process step 1.");
break;

case 2:

alert("Process step 2.");
break;

case 3:

alert("Process step 3.");
break;

default:

alert("Unexpected step encountered.");

}
// program execution continues...

Example 5

The Finite State Machine (FSM) shown in the "bad" code snippet below assigns the output ("out") based on the value of state, which is determined based on the user provided input ("user_input").

(bad code)

Example Language: Verilog

module fsm_1(out, user_input, clk, rst_n);
input [2:0] user_input;
input clk, rst_n;
output reg [2:0] out;
reg [1:0] state;
always @ (posedge clk or negedge rst_n )

begin

if (!rst_n)

state = 3'h0;

else
case (user_input)

3'h0:
3'h1:
3'h2:
3'h3: state = 2'h3;
3'h4: state = 2'h2;
3'h5: state = 2'h1;

endcase

end
out <= {1'h1, state};

endmodule

The case statement does not include a default to handle the scenario when the user provides inputs of 3'h6 and 3'h7. Those inputs push the system to an undefined state and might cause a crash (denial of service) or any other unanticipated outcome.

Adding a default statement to handle undefined inputs mitigates this issue. This is shown in the "Good" code snippet below. The default statement is in bold.

(good code)

Example Language: Verilog

case (user_input)

3'h0:
3'h1:
3'h2:
3'h3: state = 2'h3;
3'h4: state = 2'h2;
3'h5: state = 2'h1;
default: state = 2'h0;

endcase

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	962	SFP Secondary Cluster: Unchecked Status Condition
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1307	CISQ Quality Measures - Maintainability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1397	Comprehensive Categorization: Comparison

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Failure to account for default case in switch
Software Fault Patterns	SFP4		Unchecked Status Condition

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 7, "Switch Statements", Page 337. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Contributions
Contribution Date	Contributor	Organization
2022-08-15	Drew Buttner
2022-08-15	Suggested name change and other modifications, including a new demonstrative example.
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Description, Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Description, Name
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships, Type
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Applicable_Platforms, Demonstrative_Examples, Description, Name, Potential_Mitigations
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Failure to Account for Default Case in Switch

2009-05-27	Failure to Use Default Case in Switch

2022-10-13	Missing Default Case in Switch Statement

Weakness ID: 1341

View customized information:

Description

The product attempts to close or release a resource or handle more than once, without any successful open between the close operations.

Extended Description

Code typically requires "opening" handles or references to resources such as memory, files, devices, socket connections, services, etc. When the code is finished with using the resource, it is typically expected to "close" or "release" the resource, which indicates to the environment (such as the OS) that the resource can be re-assigned or reused by unrelated processes or actors - or in some cases, within the same process. API functions or other abstractions are often used to perform this release, such as free() or delete() within C/C++, or file-handle close() operations that are used in many languages.

Unfortunately, the implementation or design of such APIs might expect the developer to be responsible for ensuring that such APIs are only called once per release of the resource. If the developer attempts to release the same resource/handle more than once, then the API's expectations are not met, resulting in undefined and/or insecure behavior. This could lead to consequences such as memory corruption, data corruption, execution path corruption, or other consequences.

Note that while the implementation for most (if not all) resource reservation allocations involve a unique identifier/pointer/symbolic reference, then if this identifier is reused, checking the identifier for resource closure may result in a false state of openness and closing of the wrong resource. For this reason, reuse of identifiers is discouraged.

Common Consequences

Scope	Impact	Likelihood
Availability Integrity	Technical Impact: DoS: Crash, Exit, or Restart	Medium

Potential Mitigations

Phase: Implementation

Change the code's logic so that the resource is only closed once. This might require simplifying or refactoring. This fix can be simple to do in small code blocks, but more difficult when multiple closes are buried within complex conditionals.

Phase: Implementation

Strategy: Refactoring

It can be effective to implement a flag that is (1) set when the resource is opened, (2) cleared when it is closed, and (3) checked before closing. This approach can be useful when there are disparate cases in which closes must be performed. However, flag-tracking can increase code complexity and requires diligent compliance by the programmer.

Phase: Implementation

Strategy: Refactoring

When closing a resource, set the resource's associated variable to NULL or equivalent value for the given language. Some APIs will ignore this null value without causing errors. For other APIs, this can lead to application crashes or exceptions, which may still be preferable to corrupting an unintended resource such as memory or data.

Effectiveness: Defense in Depth

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	675	Multiple Operations on Resource in Single-Operation Context
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	415	Double Free
CanPrecede	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	672	Operation on a Resource after Expiration or Release

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	399	Resource Management Errors

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Rust (Undetermined Prevalence)

Class: Not Language-Specific (Undetermined Prevalence)

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Operating Systems

Class: Not OS-Specific (Undetermined Prevalence)

Architectures

Class: Not Architecture-Specific (Undetermined Prevalence)

Technologies

Class: Not Technology-Specific (Undetermined Prevalence)

Demonstrative Examples

Example 1

This example attempts to close a file twice. In some cases, the C library fclose() function will catch the error and return an error code. In other implementations, a double-free (CWE-415) occurs, causing the program to fault. Note that the examples presented here are simplistic, and double fclose() calls will frequently be spread around a program, making them more difficult to find during code reviews.

(bad code)

Example Language: C

char b[2000];
FILE *f = fopen("dbl_cls.c", "r");
if (f)
{

b[0] = 0;
fread(b, 1, sizeof(b) - 1, f);
printf("%s\n'", b);
int r1 = fclose(f);
printf("\n-----------------\n1 close done '%d'\n", r1);

int r2 = fclose(f); // Double close
printf("2 close done '%d'\n", r2);

}

There are multiple possible fixes. This fix only has one call to fclose(), which is typically the preferred handling of this problem - but this simplistic method is not always possible.

(good code)

Example Language: C

char b[2000];
FILE *f = fopen("dbl_cls.c", "r");
if (f)
{

b[0] = 0;
fread(b, 1, sizeof(b) - 1, f);
printf("%s\n'", b);
int r = fclose(f);
printf("\n-----------------\n1 close done '%d'\n", r);

}

This fix uses a flag to call fclose() only once. Note that this flag is explicit. The variable "f" could also have been used as it will be either NULL if the file is not able to be opened or a valid pointer if the file was successfully opened. If "f" is replacing "f_flg" then "f" would need to be set to NULL after the first fclose() call so the second fclose call would never be executed.

(good code)

Example Language: C

char b[2000];
int f_flg = 0;
FILE *f = fopen("dbl_cls.c", "r");
if (f)
{

f_flg = 1;
b[0] = 0;
fread(b, 1, sizeof(b) - 1, f);
printf("%s\n'", b);
if (f_flg)
{

int r1 = fclose(f);
f_flg = 0;
printf("\n-----------------\n1 close done '%d'\n", r1);

}

if (f_flg)
{

int r2 = fclose(f); // Double close
f_flg = 0;
printf("2 close done '%d'\n", r2);

}

Example 2

The following code shows a simple example of a double free vulnerability.

(bad code)

Example Language: C

char* ptr = (char*)malloc (SIZE);
...
if (abrt) {

free(ptr);

}
...
free(ptr);

Double free vulnerabilities have two common (and sometimes overlapping) causes:

Error conditions and other exceptional circumstances
Confusion over which part of the program is responsible for freeing the memory

Although some double free vulnerabilities are not much more complicated than this example, most are spread out across hundreds of lines of code or even different files. Programmers seem particularly susceptible to freeing global variables more than once.

Observed Examples

Reference	Description
CVE-2019-13351	file descriptor double close can cause the wrong file to be associated with a file descriptor.
CVE-2006-5051	Chain: Signal handler contains too much functionality (CWE-828), introducing a race condition that leads to a double free (CWE-415).
CVE-2004-0772	Double free resultant from certain error conditions.

Detection Methods

Automated Static Analysis

For commonly-used APIs and resource types, automated tools often have signatures that can spot this issue.

Automated Dynamic Analysis

Some compiler instrumentation tools such as AddressSanitizer (ASan) can indirectly detect some instances of this weakness.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Terminology

The terms related to "release" may vary depending on the type of resource, programming language, specification, or framework. "Close" has been used synonymously for the release of resources like file descriptors and file handles. "Return" is sometimes used instead of Release. "Free" is typically used when releasing memory or buffers back into the system for reuse.

References

[REF-1198] "close - Perldoc Browser". <https://perldoc.perl.org/functions/close>.

[REF-1199] "io - Core tools for working with streams — Python 3.9.7 documentation". 2021-09-02. <https://docs.python.org/3.9/library/io.html#io.IOBase.close>.

[REF-1200] "FileOutputStream (Java Platform SE 7 )". 2020. <https://docs.oracle.com/javase/7/docs/api/java/io/FileOutputStream.html>.

[REF-1201] "FileOutputStream (Java SE 11 & JDK 11 )". 2021. <https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/io/FileOutputStream.html>.

Content History

Submissions
Submission Date	Submitter	Organization
2021-09-07 (CWE 4.6, 2021-10-28)	CWE Content Team	MITRE
2021-09-07 (CWE 4.6, 2021-10-28)
Modifications
Modification Date	Modifier	Organization
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Demonstrative_Examples, Description, Potential_Mitigations
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated References
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 476

View customized information:

Description

The product dereferences a pointer that it expects to be valid but is NULL.

Alternate Terms

NPD:	Common abbreviation for Null Pointer Dereference
null deref:	Common abbreviation for Null Pointer Dereference
NPE:	Common abbreviation for Null Pointer Exception
nil pointer dereference:	used for access of nil in Go programs

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Crash, Exit, or Restart NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity Confidentiality	Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Potential Mitigations

Phase: Implementation

If all pointers that could have been modified are checked for NULL before use, nearly all NULL pointer dereferences can be prevented.

Phase: Requirements

Select a programming language that is not susceptible to these issues.

Phase: Implementation

Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

Effectiveness: Moderate

Note: Checking the return value of the function will typically be sufficient, however beware of race conditions (CWE-362) in a concurrent environment. This solution does not handle the use of improperly initialized variables (CWE-665).

Phase: Architecture and Design

Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.

Phase: Implementation

Explicitly initialize all variables and other data stores, either during declaration or just before the first usage.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	754	Improper Check for Unusual or Exceptional Conditions
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	710	Improper Adherence to Coding Standards
CanFollow	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	252	Unchecked Return Value
CanFollow	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	362	Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CanFollow	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	789	Memory Allocation with Excessive Size Value
CanFollow	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1325	Improperly Controlled Sequential Memory Allocation

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	465	Pointer Issues

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	754	Improper Check for Unusual or Exceptional Conditions

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Go (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

While there are no complete fixes aside from conscientious programming, the following steps will go a long way to ensure that NULL pointer dereferences do not occur.

(good code)

if (pointer1 != NULL) {

/* make use of pointer1 */
/* ... */

}

When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the if statement; and unlock when it has finished.

Example 2

This example takes an IP address from a user, verifies that it is well formed and then looks up the hostname and copies it into a buffer.

(bad code)

Example Language: C

void host_lookup(char *user_supplied_addr){

struct hostent *hp;
in_addr_t *addr;
char hostname[64];
in_addr_t inet_addr(const char *cp);

/*routine that ensures user_supplied_addr is in the right format for conversion */

validate_addr_form(user_supplied_addr);
addr = inet_addr(user_supplied_addr);
hp = gethostbyaddr( addr, sizeof(struct in_addr), AF_INET);
strcpy(hostname, hp->h_name);

}

If an attacker provides an address that appears to be well-formed, but the address does not resolve to a hostname, then the call to gethostbyaddr() will return NULL. Since the code does not check the return value from gethostbyaddr (CWE-252), a NULL pointer dereference (CWE-476) would then occur in the call to strcpy().

Note that this code is also vulnerable to a buffer overflow (CWE-119).

Example 3

In the following code, the programmer assumes that the system always has a property named "cmd" defined. If an attacker can control the program's environment so that "cmd" is not defined, the program throws a NULL pointer exception when it attempts to call the trim() method.

(bad code)

Example Language: Java

String cmd = System.getProperty("cmd");
cmd = cmd.trim();

Example 4

This Android application has registered to handle a URL when sent an intent:

(bad code)

Example Language: Java

...
IntentFilter filter = new IntentFilter("com.example.URLHandler.openURL");
MyReceiver receiver = new MyReceiver();
registerReceiver(receiver, filter);
...

public class UrlHandlerReceiver extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {

if("com.example.URLHandler.openURL".equals(intent.getAction())) {

String URL = intent.getStringExtra("URLToOpen");
int length = URL.length();

...
}

}

The application assumes the URL will always be included in the intent. When the URL is not present, the call to getStringExtra() will return null, thus causing a null pointer exception when length() is called.

Example 5

Consider the following example of a typical client server exchange. The HandleRequest function is intended to perform a request and use a defer to close the connection whenever the function returns.

(bad code)

Example Language: Go

func HandleRequest(client http.Client, request *http.Request) (*http.Response, error) {

response, err := client.Do(request)
defer response.Body.Close()
if err != nil {

return nil, err

}
...

}

If a user supplies a malformed request or violates the client policy, the Do method can return a nil response and a non-nil err.

This HandleRequest Function evaluates the close before checking the error. A deferred call's arguments are evaluated immediately, so the defer statement panics due to a nil response.

Observed Examples

Reference	Description
CVE-2005-3274	race condition causes a table to be corrupted if a timer activates while it is being modified, leading to resultant NULL dereference; also involves locking.
CVE-2002-1912	large number of packets leads to NULL dereference
CVE-2005-0772	packet with invalid error status value triggers NULL dereference
CVE-2009-4895	Chain: race condition for an argument value, possibly resulting in NULL dereference
CVE-2020-29652	ssh component for Go allows clients to cause a denial of service (nil pointer dereference) against SSH servers.
CVE-2009-2692	Chain: Use of an unimplemented network socket operation pointing to an uninitialized handler function (CWE-456) causes a crash because of a null pointer dereference (CWE-476).
CVE-2009-3547	Chain: race condition (CWE-362) might allow resource to be released before operating on it, leading to NULL dereference (CWE-476)
CVE-2009-3620	Chain: some unprivileged ioctls do not verify that a structure has been initialized before invocation, leading to NULL dereference
CVE-2009-2698	Chain: IP and UDP layers each track the same value with different mechanisms that can get out of sync, possibly resulting in a NULL dereference
CVE-2009-2692	Chain: uninitialized function pointers can be dereferenced allowing code execution
CVE-2009-0949	Chain: improper initialization of memory can lead to NULL dereference
CVE-2008-3597	Chain: game server can access player data structures before initialization has happened leading to NULL dereference
CVE-2020-6078	Chain: The return value of a function returning a pointer is not checked for success (CWE-252) resulting in the later use of an uninitialized variable (CWE-456) and a null pointer dereference (CWE-476)
CVE-2008-0062	Chain: a message having an unknown message type may cause a reference to uninitialized memory resulting in a null pointer dereference (CWE-476) or dangling pointer (CWE-825), possibly crashing the system or causing heap corruption.
CVE-2008-5183	Chain: unchecked return value can lead to NULL dereference
CVE-2004-0079	SSL software allows remote attackers to cause a denial of service (crash) via a crafted SSL/TLS handshake that triggers a null dereference.
CVE-2004-0365	Network monitor allows remote attackers to cause a denial of service (crash) via a malformed RADIUS packet that triggers a null dereference.
CVE-2003-1013	Network monitor allows remote attackers to cause a denial of service (crash) via a malformed Q.931, which triggers a null dereference.
CVE-2003-1000	Chat client allows remote attackers to cause a denial of service (crash) via a passive DCC request with an invalid ID number, which causes a null dereference.
CVE-2004-0389	Server allows remote attackers to cause a denial of service (crash) via malformed requests that trigger a null dereference.
CVE-2004-0119	OS allows remote attackers to cause a denial of service (crash from null dereference) or execute arbitrary code via a crafted request during authentication protocol selection.
CVE-2004-0458	Game allows remote attackers to cause a denial of service (server crash) via a missing argument, which triggers a null pointer dereference.
CVE-2002-0401	Network monitor allows remote attackers to cause a denial of service (crash) or execute arbitrary code via malformed packets that cause a NULL pointer dereference.
CVE-2001-1559	Chain: System call returns wrong value (CWE-393), leading to a resultant NULL dereference (CWE-476).

Weakness Ordinalities

Ordinality	Description
Resultant	(where the weakness is a quality issue that might indirectly make it easier to introduce security-relevant weaknesses or make them more difficult to detect) NULL pointer dereferences are frequently resultant from rarely encountered error conditions and race conditions, since these are most likely to escape detection during the testing phases.

Detection Methods

Automated Dynamic Analysis

Effectiveness: Moderate

Manual Dynamic Analysis

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	398	7PK - Code Quality
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	730	OWASP Top Ten 2004 Category A9 - Denial of Service
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	737	CERT C Secure Coding Standard (2008) Chapter 4 - Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	742	CERT C Secure Coding Standard (2008) Chapter 9 - Memory Management (MEM)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	808	2010 Top 25 - Weaknesses On the Cusp
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	867	2011 Top 25 - Weaknesses On the Cusp
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	871	CERT C++ Secure Coding Section 03 - Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	876	CERT C++ Secure Coding Section 08 - Memory Management (MEM)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	971	SFP Secondary Cluster: Faulty Pointer Use
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1136	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 02. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1157	SEI CERT C Coding Standard - Guidelines 03. Expressions (EXP)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1200	Weaknesses in the 2019 CWE Top 25 Most Dangerous Software Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1306	CISQ Quality Measures - Reliability
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1337	Weaknesses in the 2021 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1350	Weaknesses in the 2020 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1387	Weaknesses in the 2022 CWE Top 25 Most Dangerous Software Weaknesses
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	1425	Weaknesses in the 2023 CWE Top 25 Most Dangerous Software Weaknesses

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Null Dereference
CLASP			Null-pointer dereference
PLOVER			Null Dereference (Null Pointer Dereference)
OWASP Top Ten 2004	A9	CWE More Specific	Denial of Service
CERT C Secure Coding	EXP34-C	Exact	Do not dereference null pointers
Software Fault Patterns	SFP7		Faulty Pointer Use

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-1031] "Null pointer / Null dereferencing". Wikipedia. 2019-07-15. <https://en.wikipedia.org/wiki/Null_pointer#Null_dereferencing>.

[REF-1032] "Null Reference Creation and Null Pointer Dereference". Apple. <https://developer.apple.com/documentation/xcode/null-reference-creation-and-null-pointer-dereference>. URL validated: 2023-04-07.

[REF-1033] "NULL Pointer Dereference [CWE-476]". ImmuniWeb. 2012-09-11. <https://www.immuniweb.com/vulnerability/null-pointer-dereference.html>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Contributions
Contribution Date	Contributor	Organization
2024-02-29 (CWE 4.15, 2024-07-16)	Abhi Balakrishnan
2024-02-29 (CWE 4.15, 2024-07-16)	Provided diagram to improve CWE usability
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-01		KDM Analytics
2008-08-01	added/updated white box definitions
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Relationships
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Common_Consequences, Demonstrative_Examples, Other_Notes, Potential_Mitigations, Weakness_Ordinalities
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Potential_Mitigations, Relationships
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples, Description, Detection_Factors, Potential_Mitigations
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Demonstrative_Examples, Observed_Examples, Relationships
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Related_Attack_Patterns, Relationships
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Observed_Examples, Related_Attack_Patterns, Relationships
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Demonstrative_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Relationships
2017-01-19	CWE Content Team	MITRE
2017-01-19	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, Taxonomy_Mappings, White_Box_Definitions
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Relationships
2019-09-19	CWE Content Team	MITRE
2019-09-19	updated References, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Common_Consequences
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Demonstrative_Examples, Observed_Examples
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Relationships
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Alternate_Terms
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Alternate_Terms, Applicable_Platforms, Observed_Examples
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Demonstrative_Examples, Detection_Factors, References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes, Relationships
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples
2024-07-16 (CWE 4.15, 2024-07-16)	CWE Content Team	MITRE
2024-07-16 (CWE 4.15, 2024-07-16)	updated Alternate_Terms, Demonstrative_Examples, Description, Diagram, Potential_Mitigations, Relationships, Weakness_Ordinalities

Weakness ID: 197

View customized information:

Description

Truncation errors occur when a primitive is cast to a primitive of a smaller size and data is lost in the conversion.

Extended Description

When a primitive is cast to a smaller primitive, the high order bits of the large value are lost in the conversion, potentially resulting in an unexpected value that is not equal to the original value. This value may be required as an index into a buffer, a loop iterator, or simply necessary state data. In any case, the value cannot be trusted and the system will be in an undefined state. While this method may be employed viably to isolate the low bits of a value, this usage is rare, and truncation usually implies that an implementation error has occurred.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Memory The true value of the data is lost and corrupted data is used.

Potential Mitigations

Phase: Implementation

Ensure that no casts, implicit or explicit, take place that move from a larger size primitive or a smaller size primitive.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	681	Incorrect Conversion between Numeric Types
CanAlsoBe	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	192	Integer Coercion Error
CanAlsoBe	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	194	Unexpected Sign Extension
CanAlsoBe	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	195	Signed to Unsigned Conversion Error
CanAlsoBe	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	196	Unsigned to Signed Conversion Error

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	681	Incorrect Conversion between Numeric Types

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	681	Incorrect Conversion between Numeric Types

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Low

Demonstrative Examples

Example 1

This example, while not exploitable, shows the possible mangling of values associated with truncation errors:

(bad code)

Example Language: C

int intPrimitive;
short shortPrimitive;
intPrimitive = (int)(~((int)0) ^ (1 << (sizeof(int)*8-1)));
shortPrimitive = intPrimitive;
printf("Int MAXINT: %d\nShort MAXINT: %d\n", intPrimitive, shortPrimitive);

The above code, when compiled and run on certain systems, returns the following output:

(result)

Int MAXINT: 2147483647
Short MAXINT: -1

This problem may be exploitable when the truncated value is used as an array index, which can happen implicitly when 64-bit values are used as indexes, as they are truncated to 32 bits.

Example 2

In the following Java example, the method updateSalesForProduct is part of a business application class that updates the sales information for a particular product. The method receives as arguments the product ID and the integer amount sold. The product ID is used to retrieve the total product count from an inventory object which returns the count as an integer. Before calling the method of the sales object to update the sales count the integer values are converted to The primitive type short since the method requires short type for the method arguments.

(bad code)

Example Language: Java

...
// update sales database for number of product sold with product ID
public void updateSalesForProduct(String productID, int amountSold) {

// get the total number of products in inventory database
int productCount = inventory.getProductCount(productID);
// convert integer values to short, the method for the

// sales object requires the parameters to be of type short
short count = (short) productCount;
short sold = (short) amountSold;
// update sales database for product
sales.updateSalesCount(productID, count, sold);

}
...

However, a numeric truncation error can occur if the integer values are higher than the maximum value allowed for the primitive type short. This can cause unexpected results or loss or corruption of data. In this case the sales database may be corrupted with incorrect data. Explicit casting from a from a larger size primitive type to a smaller size primitive type should be prevented. The following example an if statement is added to validate that the integer values less than the maximum value for the primitive type short before the explicit cast and the call to the sales method.

(good code)

Example Language: Java

...
// update sales database for number of product sold with product ID
public void updateSalesForProduct(String productID, int amountSold) {

// get the total number of products in inventory database
int productCount = inventory.getProductCount(productID);
// make sure that integer numbers are not greater than

// maximum value for type short before converting
if ((productCount < Short.MAX_VALUE) && (amountSold < Short.MAX_VALUE)) {

// convert integer values to short, the method for the

// sales object requires the parameters to be of type short
short count = (short) productCount;
short sold = (short) amountSold;
// update sales database for product
sales.updateSalesCount(productID, count, sold);

else {
// throw exception or perform other processing

...

}

}
...

Observed Examples

Reference	Description
CVE-2020-17087	Chain: integer truncation (CWE-197) causes small buffer allocation (CWE-131) leading to out-of-bounds write (CWE-787) in kernel pool, as exploited in the wild per CISA KEV.
CVE-2009-0231	Integer truncation of length value leads to heap-based buffer overflow.
CVE-2008-3282	Size of a particular type changes for 64-bit platforms, leading to an integer truncation in document processor causes incorrect index to be generated.

Detection Methods

Fuzzing

Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.

Effectiveness: High

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	738	CERT C Secure Coding Standard (2008) Chapter 5 - Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	848	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 5 - Numeric Types and Operations (NUM)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	872	CERT C++ Secure Coding Section 04 - Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	998	SFP Secondary Cluster: Glitch in Computation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1137	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 03. Numeric Types and Operations (NUM)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1158	SEI CERT C Coding Standard - Guidelines 04. Integers (INT)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1159	SEI CERT C Coding Standard - Guidelines 05. Floating Point (FLP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1163	SEI CERT C Coding Standard - Guidelines 09. Input Output (FIO)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Research Gap

This weakness has traditionally been under-studied and under-reported, although vulnerabilities in popular software have been published in 2008 and 2009.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Numeric truncation error
CLASP			Truncation error
CERT C Secure Coding	FIO34-C	CWE More Abstract	Distinguish between characters read from a file and EOF or WEOF
CERT C Secure Coding	FLP34-C	CWE More Abstract	Ensure that floating point conversions are within range of the new type
CERT C Secure Coding	INT02-C		Understand integer conversion rules
CERT C Secure Coding	INT05-C		Do not use input functions to convert character data if they cannot handle all possible inputs
CERT C Secure Coding	INT31-C	CWE More Abstract	Ensure that integer conversions do not result in lost or misinterpreted data
The CERT Oracle Secure Coding Standard for Java (2011)	NUM12-J		Ensure conversions of numeric types to narrower types do not result in lost or misinterpreted data
Software Fault Patterns	SFP1		Glitch in computation

References

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 6, "Truncation", Page 259. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	PLOVER
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Description, Observed_Examples, Other_Notes, Research_Gaps
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2022-06-28	CWE Content Team	MITRE
2022-06-28	updated Observed_Examples
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 581

View customized information:

Description

The product does not maintain equal hashcodes for equal objects.

Extended Description

Java objects are expected to obey a number of invariants related to equality. One of these invariants is that equal objects must have equal hashcodes. In other words, if a.equals(b) == true then a.hashCode() == b.hashCode().

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Other If this invariant is not upheld, it is likely to cause trouble if objects of this class are stored in a collection. If the objects of the class in question are used as a key in a Hashtable or if they are inserted into a Map or Set, it is critical that equal objects have equal hashcodes.

Potential Mitigations

Phase: Implementation

Both Equals() and Hashcode() should be defined.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	697	Incorrect Comparison
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1006	Bad Coding Practices

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	850	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 7 - Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	977	SFP Secondary Cluster: Design
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1140	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 06. Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	MET09-J		Classes that define an equals() method must also define a hashCode() method

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Relationships, Other_Notes
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Common_Consequences, Description, Other_Notes
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Common_Consequences
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Description
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Type
Previous Entry Names
Change Date	Previous Entry Name
2008-01-30	Object Model Violation: Just One of Equals and Haschode Defined

Weakness ID: 484

View customized information:

Description

The product omits a break statement within a switch or similar construct, causing code associated with multiple conditions to execute. This can cause problems when the programmer only intended to execute code associated with one condition.

Extended Description

This can lead to critical code executing in situations where it should not.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Alter Execution Logic This weakness can cause unintended logic to be executed and other unexpected application behavior.

Potential Mitigations

Phase: Implementation

Omitting a break statement so that one may fall through is often indistinguishable from an error, and therefore should be avoided. If you need to use fall-through capabilities, make sure that you have clearly documented this within the switch statement, and ensure that you have examined all the logical possibilities.

Phase: Implementation

The functionality of omitting a break statement could be clarified with an if statement. This method is much safer.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	670	Always-Incorrect Control Flow Implementation
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	710	Improper Adherence to Coding Standards

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	438	Behavioral Problems

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

In both of these examples, a message is printed based on the month passed into the function:

(bad code)

Example Language: Java

public void printMessage(int month){

switch (month) {

case 1: print("January");
case 2: print("February");
case 3: print("March");
case 4: print("April");
case 5: print("May");
case 6: print("June");
case 7: print("July");
case 8: print("August");
case 9: print("September");
case 10: print("October");
case 11: print("November");
case 12: print("December");

}
println(" is a great month");

}

(bad code)

Example Language: C

void printMessage(int month){

switch (month) {

case 1: printf("January");
case 2: printf("February");
case 3: printf("March");
case 4: printf("April");
case 5: printff("May");
case 6: printf("June");
case 7: printf("July");
case 8: printf("August");
case 9: printf("September");
case 10: printf("October");
case 11: printf("November");
case 12: printf("December");

}
printf(" is a great month");

}

Both examples do not use a break statement after each case, which leads to unintended fall-through behavior. For example, calling "printMessage(10)" will result in the text "OctoberNovemberDecember is a great month" being printed.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)
Indirect	(where the weakness is a quality issue that might indirectly make it easier to introduce security-relevant weaknesses or make them more difficult to detect)

Detection Methods

White Box

Omission of a break statement might be intentional, in order to support fallthrough. Automated detection methods might therefore be erroneous. Semantic understanding of expected product behavior is required to interpret whether the code is correct.

Black Box

Since this weakness is associated with a code construct, it would be indistinguishable from other errors that produce the same behavior.

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	962	SFP Secondary Cluster: Unchecked Status Condition
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1306	CISQ Quality Measures - Reliability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1307	CISQ Quality Measures - Maintainability
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Omitted break statement
Software Fault Patterns	SFP4		Unchecked Status Condition

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 7, "Switch Statements", Page 337. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Description, Detection_Factors, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Applicable_Platforms, Demonstrative_Examples, Description, Detection_Factors, Name, Other_Notes, Potential_Mitigations, Weakness_Ordinalities
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, References, Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Weakness_Ordinalities
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description, Detection_Factors
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-11-24	Omitted Break Statement

Weakness ID: 374

View customized information:

Description

The product sends non-cloned mutable data as an argument to a method or function.

Extended Description

The function or method that has been called can alter or delete the mutable data. This could violate assumptions that the calling function has made about its state. In situations where unknown code is called with references to mutable data, this external code could make changes to the data sent. If this data was not previously cloned, the modified data might not be valid in the context of execution.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Memory Potentially data could be tampered with by another function which should not have been tampered with.

Potential Mitigations

Phase: Implementation

Pass in data which should not be altered as constant or immutable.

Phase: Implementation

Clone all mutable data before passing it into an external function . This is the preferred mitigation. This way, regardless of what changes are made to the data, a valid copy is retained for use by the class.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	371	State Issues

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following example demonstrates the weakness.

(bad code)

Example Language: C

private:

int foo;
complexType bar;
String baz;
otherClass externalClass;

public:

void doStuff() {

externalClass.doOtherStuff(foo, bar, baz)

}

In this example, bar and baz will be passed by reference to doOtherStuff() which may change them.

Example 2

In the following Java example, the BookStore class manages the sale of books in a bookstore, this class includes the member objects for the bookstore inventory and sales database manager classes. The BookStore class includes a method for updating the sales database and inventory when a book is sold. This method retrieves a Book object from the bookstore inventory object using the supplied ISBN number for the book class, then calls a method for the sales object to update the sales information and then calls a method for the inventory object to update inventory for the BookStore.

(bad code)

Example Language: Java

public class BookStore {

private BookStoreInventory inventory;
private SalesDBManager sales;
...
// constructor for BookStore
public BookStore() {

this.inventory = new BookStoreInventory();
this.sales = new SalesDBManager();
...

}
public void updateSalesAndInventoryForBookSold(String bookISBN) {

// Get book object from inventory using ISBN
Book book = inventory.getBookWithISBN(bookISBN);
// update sales information for book sold
sales.updateSalesInformation(book);
// update inventory
inventory.updateInventory(book);

}
// other BookStore methods
...

}
public class Book {

private String title;
private String author;
private String isbn;
// Book object constructors and get/set methods
...

}

However, in this example the Book object that is retrieved and passed to the method of the sales object could have its contents modified by the method. This could cause unexpected results when the book object is sent to the method for the inventory object to update the inventory.

In the Java programming language arguments to methods are passed by value, however in the case of objects a reference to the object is passed by value to the method. When an object reference is passed as a method argument a copy of the object reference is made within the method and therefore both references point to the same object. This allows the contents of the object to be modified by the method that holds the copy of the object reference. [REF-374]

In this case the contents of the Book object could be modified by the method of the sales object prior to the call to update the inventory.

To prevent the contents of the Book object from being modified, a copy of the Book object should be made before the method call to the sales object. In the following example a copy of the Book object is made using the clone() method and the copy of the Book object is passed to the method of the sales object. This will prevent any changes being made to the original Book object.

(good code)

Example Language: Java

...
public void updateSalesAndInventoryForBookSold(String bookISBN) {

// Get book object from inventory using ISBN
Book book = inventory.getBookWithISBN(bookISBN);
// Create copy of book object to make sure contents are not changed
Book bookSold = (Book) book.clone();
// update sales information for book sold
sales.updateSalesInformation(bookSold);
// update inventory
inventory.updateInventory(book);

}
...

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Passing mutable objects to an untrusted method
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ04-J	Provide mutable classes with copy functionality to safely allow passing instances to untrusted code
Software Fault Patterns	SFP23	Exposed Data

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-374] Tony Sintes. "Does Java pass by reference or pass by value?". JavaWorld.com. 2000-05-26. <https://web.archive.org/web/20000619025001/https://www.javaworld.com/javaworld/javaqa/2000-05/03-qa-0526-pass.html>. URL validated: 2023-04-07.

[REF-375] Herbert Schildt. "Java: The Complete Reference, J2SE 5th Edition".

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Name, Taxonomy_Mappings
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Demonstrative_Examples, Description, Other_Notes, Potential_Mitigations, References
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated References, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2010-06-21	Mutable Objects Passed by Reference

Weakness ID: 495

View customized information:

Description

The product has a method that is declared public, but returns a reference to a private data structure, which could then be modified in unexpected ways.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data The contents of the data structure can be modified from outside the intended scope.

Potential Mitigations

Phase: Implementation

Declare the method private.

Phase: Implementation

Clone the member data and keep an unmodified version of the data private to the object.

Phase: Implementation

Use public setter methods that govern how a private member can be modified.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	664	Improper Control of a Resource Through its Lifetime

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Demonstrative Examples

Example 1

Here, a public method in a Java class returns a reference to a private array. Given that arrays in Java are mutable, any modifications made to the returned reference would be reflected in the original private array.

(bad code)

Example Language: Java

private String[] colors;
public String[] getColors() {

return colors;

}

Example 2

In this example, the Color class defines functions that return non-const references to private members (an array type and an integer type), which are then arbitrarily altered from outside the control of the class.

(bad code)

Example Language: C++

class Color
{

private:

int[2] colorArray;
int colorValue;

public:

Color () : colorArray { 1, 2 }, colorValue (3) { };
int[2] & fa () { return colorArray; } // return reference to private array
int & fv () { return colorValue; } // return reference to private integer

};

int main ()
{

Color c;

c.fa () [1] = 42; // modifies private array element
c.fv () = 42; // modifies private int

return 0;

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Private Array-Typed Field Returned From A Public Method
Software Fault Patterns	SFP23		Exposed Data

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-01		KDM Analytics
2008-08-01	added/updated white box definitions
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, White_Box_Definitions
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Common_Consequences, Demonstrative_Examples, Description, Name, Potential_Mitigations
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2019-01-03	Private Array-Typed Field Returned From A Public Method

Weakness ID: 491

View customized information:

Description

A class has a cloneable() method that is not declared final, which allows an object to be created without calling the constructor. This can cause the object to be in an unexpected state.

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Unexpected State; Varies by Context

Potential Mitigations

Phase: Implementation

Make the cloneable() method final.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In this example, a public class "BankAccount" implements the cloneable() method which declares "Object clone(string accountnumber)":

(bad code)

Example Language: Java

public class BankAccount implements Cloneable{

public Object clone(String accountnumber) throws
CloneNotSupportedException
{

Object returnMe = new BankAccount(account number);
...

}

Example 2

In the example below, a clone() method is defined without being declared final.

(bad code)

Example Language: Java

protected Object clone() throws CloneNotSupportedException {

...

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Mobile Code: Object Hijack
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ07-J	Sensitive classes must not let themselves be copied
Software Fault Patterns	SFP28	Unexpected access points

References

[REF-453] OWASP. "OWASP , Attack Category : Mobile code: object hijack". <http://www.owasp.org/index.php/Mobile_code:_object_hijack>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated References, Demonstrative_Example, Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, References, Taxonomy_Mappings
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Name
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Mobile Code: Object Hijack

2009-05-27	Public cloneable() Method Without Final (aka 'Object Hijack')

Weakness ID: 496

View customized information:

Description

Assigning public data to a private array is equivalent to giving public access to the array.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data The contents of the array can be modified from outside the intended scope.

Potential Mitigations

Phase: Implementation

Do not allow objects to modify private members of a class.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	664	Improper Control of a Resource Through its Lifetime

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the example below, the setRoles() method assigns a publically-controllable array to a private field, thus allowing the caller to modify the private array directly by virtue of the fact that arrays in Java are mutable.

(bad code)

Example Language: Java

private String[] userRoles;
public void setUserRoles(String[] userRoles) {

this.userRoles = userRoles;

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	994	SFP Secondary Cluster: Tainted Input to Variable
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Public Data Assigned to Private Array-Typed Field
Software Fault Patterns	SFP25		Tainted input to variable

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-01		KDM Analytics
2008-08-01	added/updated white box definitions
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, White_Box_Definitions
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 500

View customized information:

Description

An object contains a public static field that is not marked final, which might allow it to be modified in unexpected ways.

Extended Description

Public static variables can be read without an accessor and changed without a mutator by any classes in the application.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data The object could potentially be tampered with.
Confidentiality	Technical Impact: Read Application Data The object could potentially allow the object to be read.

Potential Mitigations

Phase: Architecture and Design

Clearly identify the scope for all critical data elements, including whether they should be regarded as static.

Phase: Implementation

Make any static fields private and constant.

A constant field is denoted by the keyword 'const' in C/C++ and ' final' in Java

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	493	Critical Public Variable Without Final Modifier

Background Details

When a field is declared public but not final, the field can be read and written to by arbitrary Java code.

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

The following examples use of a public static String variable to contain the name of a property/configuration file for the application.

(bad code)

Example Language: C++

class SomeAppClass {

public:

static string appPropertiesConfigFile = "app/properties.config";

...

}

(bad code)

Example Language: Java

public class SomeAppClass {

public static String appPropertiesFile = "app/Application.properties";
...

}

Having a public static variable that is not marked final (constant) may allow the variable to the altered in a way not intended by the application. In this example the String variable can be modified to indicate a different on nonexistent properties file which could cause the application to crash or caused unexpected behavior.

(good code)

Example Language: C++

class SomeAppClass {

public:

static const string appPropertiesConfigFile = "app/properties.config";

...

}

(good code)

Example Language: Java

public class SomeAppClass {

public static final String appPropertiesFile = "app/Application.properties";
...

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Overflow of static internal buffer
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ10-J	Do not use public static nonfinal variables
Software Fault Patterns	SFP28	Unexpected access points

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-01		KDM Analytics
2008-08-01	added/updated white box definitions
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2008-11-05	CWE Content Team	MITRE
2008-11-05	Significant clarification of this entry, and improved examples.
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Background_Details, Demonstrative_Examples, Description, Name, Other_Notes, Potential_Mitigations
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples, Description, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated White_Box_Definitions
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Overflow of Static Internal Buffer

2008-11-24	Static Field Not Marked Final

Weakness ID: 607

View customized information:

Description

A public or protected static final field references a mutable object, which allows the object to be changed by malicious code, or accidentally from another package.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Modify Application Data

Potential Mitigations

Phase: Implementation

Protect mutable objects by making them private. Restrict access to the getter and setter as well.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	471	Modification of Assumed-Immutable Data (MAID)

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

Here, an array (which is inherently mutable) is labeled public static final.

(bad code)

Example Language: Java

public static final String[] USER_ROLES;

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP23		Exposed Data

Content History

Submissions
Submission Date	Submitter	Organization
2007-05-07 (CWE Draft 6, 2007-05-07)	Anonymous Tool Vendor (under NDA)
2007-05-07 (CWE Draft 6, 2007-05-07)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Sean Eidemiller	Cigital
2008-07-01	added/updated demonstrative examples
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 366

View customized information:

Description

If two threads of execution use a resource simultaneously, there exists the possibility that resources may be used while invalid, in turn making the state of execution undefined.

Common Consequences

Scope	Impact	Likelihood
Integrity Other	Technical Impact: Alter Execution Logic; Unexpected State The main problem is that -- if a lock is overcome -- data could be altered in a bad state.

Potential Mitigations

Phase: Architecture and Design

Use locking functionality. This is the recommended solution. Implement some form of locking mechanism around code which alters or reads persistent data in a multithreaded environment.

Phase: Architecture and Design

Create resource-locking validation checks. If no inherent locking mechanisms exist, use flags and signals to enforce your own blocking scheme when resources are being used by other threads of execution.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	362	Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	557	Concurrency Issues

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following example demonstrates the weakness.

(bad code)

Example Language: C

int foo = 0;
int storenum(int num) {

static int counter = 0;
counter++;
if (num > foo) foo = num;
return foo;

}

(bad code)

Example Language: Java

public classRace {

static int foo = 0;
public static void main() {

new Threader().start();
foo = 1;

}
public static class Threader extends Thread {

public void run() {

System.out.println(foo);

}

Observed Examples

Reference	Description
CVE-2022-2621	Chain: two threads in a web browser use the same resource (CWE-366), but one of those threads can destroy the resource before the other has completed (CWE-416).

Detection Methods

Automated Static Analysis

Effectiveness: High

Affected Resources

System Process

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	748	CERT C Secure Coding Standard (2008) Appendix - POSIX (POS)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	852	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 9 - Visibility and Atomicity (VNA)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	882	CERT C++ Secure Coding Section 14 - Concurrency (CON)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	986	SFP Secondary Cluster: Missing Lock
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1142	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 08. Visibility and Atomicity (VNA)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1169	SEI CERT C Coding Standard - Guidelines 14. Concurrency (CON)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Race condition within a thread
CERT C Secure Coding	CON32-C	CWE More Abstract	Prevent data races when accessing bit-fields from multiple threads
CERT C Secure Coding	CON40-C	CWE More Abstract	Do not refer to an atomic variable twice in an expression
CERT C Secure Coding	CON43-C	Exact	Do not allow data races in multithreaded code
The CERT Oracle Secure Coding Standard for Java (2011)	VNA02-J		Ensure that compound operations on shared variables are atomic
The CERT Oracle Secure Coding Standard for Java (2011)	VNA03-J		Do not assume that a group of calls to independently atomic methods is atomic
Software Fault Patterns	SFP19		Missing Lock

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-26	Leveraging Race Conditions
CAPEC-29	Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 13: Race Conditions." Page 205. McGraw-Hill. 2010.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 13, "Race Conditions", Page 759. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Taxonomy_Mappings
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Relationships, Taxonomy_Mappings
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Potential_Mitigations, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Potential_Mitigations
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples

Weakness ID: 487

View customized information:

Description

Java packages are not inherently closed; therefore, relying on them for code security is not a good practice.

Extended Description

The purpose of package scope is to prevent accidental access by other parts of a program. This is an ease-of-software-development feature but not a security feature.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data Any data in a Java package can be accessed outside of the Java framework if the package is distributed.
Integrity	Technical Impact: Modify Application Data The data in a Java class can be modified by anyone outside of the Java framework if the packages is distributed.

Potential Mitigations

Phases: Architecture and Design; Implementation

Data should be private static and final whenever possible. This will assure that your code is protected by instantiating early, preventing access and tampering.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	664	Improper Control of a Resource Through its Lifetime

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1006	Bad Coding Practices

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following example demonstrates the weakness.

(bad code)

Example Language: Java

package math;
public class Lebesgue implements Integration{

public final Static String youAreHidingThisFunction(functionToIntegrate){

return ...;

}

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	850	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 7 - Methods (MET)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	966	SFP Secondary Cluster: Other Exposures
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1416	Comprehensive Categorization: Resource Lifecycle Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Relying on package-level scope
The CERT Oracle Secure Coding Standard for Java (2011)	MET04-J		Do not increase the accessibility of overridden or hidden methods

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Demonstrative_Examples, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Type
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Relying on Package-level Scope

Weakness ID: 375

View customized information:

Description

Sending non-cloned mutable data as a return value may result in that data being altered or deleted by the calling function.

Extended Description

In situations where functions return references to mutable data, it is possible that the external code which called the function may make changes to the data sent. If this data was not previously cloned, the class will then be using modified data which may violate assumptions about its internal state.

Common Consequences

Scope	Impact	Likelihood
Access Control Integrity	Technical Impact: Modify Memory Potentially data could be tampered with by another function which should not have been tampered with.

Potential Mitigations

Phase: Implementation

Declare returned data which should not be altered as constant or immutable.

Phase: Implementation

Clone all mutable data before returning references to it. This is the preferred mitigation. This way, regardless of what changes are made to the data, a valid copy is retained for use by the class.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	371	State Issues

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

This class has a private list of patients, but provides a way to see the list :

(bad code)

Example Language: Java

public class ClinicalTrial {

private PatientClass[] patientList = new PatientClass[50];
public getPatients(...){

return patientList;

}

While this code only means to allow reading of the patient list, the getPatients() method returns a reference to the class's original patient list instead of a reference to a copy of the list. Any caller of this method can arbitrarily modify the contents of the patient list even though it is a private member of the class.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1181	SEI CERT Perl Coding Standard - Guidelines 03. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
CLASP			Mutable object returned
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ04-J		Provide mutable classes with copy functionality to safely allow passing instances to untrusted code
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ05-J		Defensively copy private mutable class members before returning their references
SEI CERT Perl Coding Standard	EXP34-PL	Imprecise	Do not modify $_ in list or sorting functions
Software Fault Patterns	SFP23		Exposed Data

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Name, Taxonomy_Mappings
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2010-09-27	Passing Mutable Objects to an Untrusted Method

Weakness ID: 499

View customized information:

Description

The code contains a class with sensitive data, but the class does not explicitly deny serialization. The data can be accessed by serializing the class through another class.

Extended Description

Serializable classes are effectively open classes since data cannot be hidden in them. Classes that do not explicitly deny serialization can be serialized by any other class, which can then in turn use the data stored inside it.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data an attacker can write out the class to a byte stream, then extract the important data from it.

Potential Mitigations

Phase: Implementation

In Java, explicitly define final writeObject() to prevent serialization. This is the recommended solution. Define the writeObject() function to throw an exception explicitly denying serialization.

Phase: Implementation

Make sure to prevent serialization of your objects.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere
CanPrecede	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	200	Exposure of Sensitive Information to an Unauthorized Actor

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

This code creates a new record for a medical patient:

(bad code)

Example Language: Java

class PatientRecord {

private String name;
private String socialSecurityNum;
public Patient(String name,String ssn) {

this.SetName(name);
this.SetSocialSecurityNumber(ssn);

}

This object does not explicitly deny serialization, allowing an attacker to serialize an instance of this object and gain a patient's name and Social Security number even though those fields are private.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	858	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 15 - Serialization (SER)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	963	SFP Secondary Cluster: Exposed Data
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1148	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 14. Serialization (SER)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
CLASP		Information leak through serialization
The CERT Oracle Secure Coding Standard for Java (2011)	SER03-J	Do not serialize unencrypted, sensitive data
The CERT Oracle Secure Coding Standard for Java (2011)	SER05-J	Do not serialize instances of inner classes
Software Fault Patterns	SFP23	Exposed Data

References

[REF-18] Secure Software, Inc.. "The CLASP Application Security Process". 2005. <https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	CLASP
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Description, Relationships, Taxonomy_Mappings
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Demonstrative_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Information Leak through Serialization

Weakness ID: 102

View customized information:

Description

The product uses multiple validation forms with the same name, which might cause the Struts Validator to validate a form that the programmer does not expect.

Extended Description

If two validation forms have the same name, the Struts Validator arbitrarily chooses one of the forms to use for input validation and discards the other. This decision might not correspond to the programmer's expectations, possibly leading to resultant weaknesses. Moreover, it indicates that the validation logic is not up-to-date, and can indicate that other, more subtle validation errors are present.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Unexpected State

Potential Mitigations

Phase: Implementation

The DTD or schema validation will not catch the duplicate occurrence of the same form name. To find the issue in the implementation, manual checks or automated static analysis could be applied to the xml configuration files.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1173	Improper Use of Validation Framework
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	694	Use of Multiple Resources with Duplicate Identifier
PeerOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	675	Multiple Operations on Resource in Single-Operation Context

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

These two Struts validation forms have the same name.

(bad code)

Example Language: XML

<form-validation>

</formset>

</form-validation>

It is not certain which form will be used by Struts. It is critically important that validation logic be maintained and kept in sync with the rest of the product.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	722	OWASP Top Ten 2004 Category A1 - Unvalidated Input
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1409	Comprehensive Categorization: Injection

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Duplicate Validation Forms
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Demonstrative_Example, Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description, Other_Notes, Potential_Mitigations
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Background_Details, Common_Consequences, Other_Notes
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Background_Details, Common_Consequences
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Demonstrative_Examples, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples

Weakness ID: 104

View customized information:

Description

If a form bean does not extend an ActionForm subclass of the Validator framework, it can expose the application to other weaknesses related to insufficient input validation.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Other Bypassing the validation framework for a form exposes the application to numerous types of attacks. Unchecked input is an important component of vulnerabilities like cross-site scripting, process control, and SQL injection.
Confidentiality Integrity Availability Other	Technical Impact: Other Although J2EE applications are not generally susceptible to memory corruption attacks, if a J2EE application interfaces with native code that does not perform array bounds checking, an attacker may be able to use an input validation mistake in the J2EE application to launch a buffer overflow attack.

Potential Mitigations

Phase: Implementation

Ensure that all forms extend one of the Validation Classes.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Background Details

In order to use the Struts Validator, a form must extend one of the following: ValidatorForm, ValidatorActionForm, DynaValidatorActionForm, and DynaValidatorForm. One of these classes must be extended because the Struts Validator ties in to the application by implementing the validate() method in these classes. Forms derived from the ActionForm and DynaActionForm classes cannot use the Struts Validator.

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user information from a registration webpage for an online business site. The user will enter registration data and through the Struts framework the RegistrationForm bean will maintain the user data.

(bad code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.action.ActionForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

// getter and setter methods for private variables
...

}

However, the RegistrationForm class extends the Struts ActionForm class which does not allow the RegistrationForm class to use the Struts validator capabilities. When using the Struts framework to maintain user data in an ActionForm Bean, the class should always extend one of the validator classes, ValidatorForm, ValidatorActionForm, DynaValidatorForm or DynaValidatorActionForm. These validator classes provide default validation and the validate method for custom validation for the Bean object to use for validating input data. The following Java example shows the RegistrationForm class extending the ValidatorForm class and implementing the validate method for validating input data.

(good code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {...}

// getter and setter methods for private variables
...

}

Note that the ValidatorForm class itself extends the ActionForm class within the Struts framework API.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	722	OWASP Top Ten 2004 Category A1 - Unvalidated Input
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Form Bean Does Not Extend Validation Class
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Background_Details, Common_Consequences, Other_Notes
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Common_Consequences, Other_Notes
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Background_Details
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 105

View customized information:

Description

The product has a form field that is not validated by a corresponding validation form, which can introduce other weaknesses related to insufficient input validation.

Extended Description

Omitting validation for even a single input field may give attackers the leeway they need to compromise the product. Although J2EE applications are not generally susceptible to memory corruption attacks, if a J2EE application interfaces with native code that does not perform array bounds checking, an attacker may be able to use an input validation mistake in the J2EE application to launch a buffer overflow attack.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Unexpected State
Integrity	Technical Impact: Bypass Protection Mechanism If unused fields are not validated, shared business logic in an action may allow attackers to bypass the validation checks that are performed for other uses of the form.

Potential Mitigations

Phase: Implementation

Validate all form fields. If a field is unused, it is still important to constrain it so that it is empty or undefined.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1173	Improper Use of Validation Framework

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation	Some products use the same ActionForm for more than one purpose. In situations like this, some fields may go unused under some action mappings.

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following example the Java class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and, through the Struts framework, the RegistrationForm bean will maintain the user data in the form fields using the private member variables. The RegistrationForm class uses the Struts validation capability by extending the ValidatorForm class and including the validation for the form fields within the validator XML file, validator.xml.

(result)

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String address;
private String city;
private String state;
private String zipcode;
private String phone;
private String email;

public RegistrationForm() {

super();

}

// getter and setter methods for private variables
...

}

The validator XML file, validator.xml, provides the validation for the form fields of the RegistrationForm.

(bad code)

Example Language: XML

<form-validation>

</field>
<field property="address" depends="required">

</field>
<field property="city" depends="required">

</field>
<field property="state" depends="required,mask">

<var-name>mask</var-name>
<var-value>[a-zA-Z]{2}</var-value>

</var>

</field>
<field property="zipcode" depends="required,mask">

<var-name>mask</var-name>
<var-value>\d{5}</var-value>

</var>

</field>

</form>

</formset>

</form-validation>

However, in the previous example the validator XML file, validator.xml, does not provide validators for all of the form fields in the RegistrationForm. Validator forms are only provided for the first five of the seven form fields. The validator XML file should contain validator forms for all of the form fields for a Struts ActionForm bean. The following validator.xml file for the RegistrationForm class contains validator forms for all of the form fields.

(good code)

Example Language: XML

<form-validation>

</field>
<field property="address" depends="required">

</field>
<field property="city" depends="required">

</field>
<field property="state" depends="required,mask">

<var-name>mask</var-name>
<var-value>[a-zA-Z]{2}</var-value>

</var>

</field>
<field property="zipcode" depends="required,mask">

<var-name>mask</var-name>
<var-value>\d{5}</var-value>

</var>

</field>
<field property="phone" depends="required,mask">

<var-name>mask</var-name>
<var-value>^([0-9]{3})(-)([0-9]{4}|[0-9]{4})$</var-value>

</var>

</field>
<field property="email" depends="required,email">

</field>

</form>

</formset>

</form-validation>

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1406	Comprehensive Categorization: Improper Input Validation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Form Field Without Validator
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Common_Consequences, Description, Modes_of_Introduction, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Potential_Mitigations
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description, Modes_of_Introduction
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 103

View customized information:

Description

The product has a validator form that either does not define a validate() method, or defines a validate() method but does not call super.validate().

Extended Description

If the code does not call super.validate(), the Validation Framework cannot check the contents of the form against a validation form. In other words, the validation framework will be disabled for the given form.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Other Disabling the validation framework for a form exposes the product to numerous types of attacks. Unchecked input is the root cause of vulnerabilities like cross-site scripting, process control, and SQL injection.
Confidentiality Integrity Availability Other	Technical Impact: Other Although J2EE applications are not generally susceptible to memory corruption attacks, if a J2EE application interfaces with native code that does not perform array bounds checking, an attacker may be able to use an input validation mistake in the J2EE application to launch a buffer overflow attack.

Potential Mitigations

Phase: Implementation

Implement the validate() method and call super.validate() within that method.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	573	Improper Following of Specification by Caller

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Background Details

The Struts Validator uses a form's validate() method to check the contents of the form properties against the constraints specified in the associated validation form. That means the following classes have a validate() method that is part of the validation framework: ValidatorForm, ValidatorActionForm, DynaValidatorForm, and DynaValidatorActionForm. If the code creates a class that extends one of these classes, and if that class implements custom validation logic by overriding the validate() method, the code must call super.validate() in the validate() implementation.

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and the RegistrationForm bean in the Struts framework will maintain the user data. Tthe RegistrationForm class implements the validate method to validate the user input entered into the form.

(bad code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {

ActionErrors errors = new ActionErrors();
if (getName() == null || getName().length() < 1) {

errors.add("name", new ActionMessage("error.name.required"));

}
return errors;

}

// getter and setter methods for private variables
...

}

Although the validate method is implemented in this example the method does not call the validate method of the ValidatorForm parent class with a call super.validate(). Without the call to the parent validator class only the custom validation will be performed and the default validation will not be performed. The following example shows that the validate method of the ValidatorForm class is called within the implementation of the validate method.

(good code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {

ActionErrors errors = super.validate(mapping, request);
if (errors == null) {

errors = new ActionErrors();

}

if (getName() == null || getName().length() < 1) {

errors.add("name", new ActionMessage("error.name.required"));

}
return errors;

}

// getter and setter methods for private variables
...

}

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	722	OWASP Top Ten 2004 Category A1 - Unvalidated Input
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Relationship

This could introduce other weaknesses related to missing input validation.

Maintenance

The current description implies a loose composite of two separate weaknesses, so this node might need to be split or converted into a low-level category.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Erroneous validate() Method
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description, Maintenance_Notes
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Background_Details, Common_Consequences, Description, Other_Notes, Relationship_Notes
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Common_Consequences, Other_Notes
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Description
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Background_Details, Description
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Common_Consequences, Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 608

View customized information:

Description

An ActionForm class contains a field that has not been declared private, which can be accessed without using a setter or getter.

Common Consequences

Scope	Impact	Likelihood
Integrity Confidentiality	Technical Impact: Modify Application Data; Read Application Data

Potential Mitigations

Phase: Implementation

Make all fields private. Use getter to get the value of the field. Setter should be used only by the framework; setting an action form field from other actions is bad practice and should be avoided.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for a online business site. The user will enter registration data and through the Struts framework the RegistrationForm bean will maintain the user data.

(bad code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// variables for registration form
public String name;
public String email;
...

public RegistrationForm() {

super();

}
public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {...}
...

}

However, within the RegistrationForm the member variables for the registration form input data are declared public not private. All member variables within a Struts framework ActionForm class must be declared private to prevent the member variables from being modified without using the getter and setter methods. The following example shows the member variables being declared private and getter and setter methods declared for accessing the member variables.

(good code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {...}

// getter and setter methods for private variables
...

}

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1002	SFP Secondary Cluster: Unexpected Entry Points
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP28		Unexpected access points

Content History

Submissions
Submission Date	Submitter	Organization
2007-05-07 (CWE Draft 6, 2007-05-07)	Anonymous Tool Vendor (under NDA)
2007-05-07 (CWE Draft 6, 2007-05-07)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Taxonomy_Mappings, Weakness_Ordinalities
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 106

View customized information:

Description

When an application does not use an input validation framework such as the Struts Validator, there is a greater risk of introducing weaknesses related to insufficient input validation.

Extended Description

Unchecked input is the leading cause of vulnerabilities in J2EE applications. Unchecked input leads to cross-site scripting, process control, and SQL injection vulnerabilities, among others.

Although J2EE applications are not generally susceptible to memory corruption attacks, if a J2EE application interfaces with native code that does not perform array bounds checking, an attacker may be able to use an input validation mistake in the J2EE application to launch a buffer overflow attack.

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Unexpected State

Potential Mitigations

Phase: Architecture and Design

Strategy: Input Validation

Use an input validation framework such as Struts.

Phase: Architecture and Design

Strategy: Libraries or Frameworks

Use an input validation framework such as Struts.

Phase: Implementation

Strategy: Input Validation

Use the Struts Validator to validate all program input before it is processed by the application. Ensure that there are no holes in the configuration of the Struts Validator. Example uses of the validator include checking to ensure that:

Phone number fields contain only valid characters in phone numbers

Boolean values are only "T" or "F"

Free-form strings are of a reasonable length and composition

Phase: Implementation

Strategy: Libraries or Frameworks

Phone number fields contain only valid characters in phone numbers

Boolean values are only "T" or "F"

Free-form strings are of a reasonable length and composition

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1173	Improper Use of Validation Framework

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following Java example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and, through the Struts framework, the RegistrationForm bean will maintain the user data.

(bad code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.action.ActionForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

// getter and setter methods for private variables
...

}

However, the RegistrationForm class extends the Struts ActionForm class which does use the Struts validator plug-in to provide validator capabilities. In the following example, the RegistrationForm Java class extends the ValidatorForm and Struts configuration XML file, struts-config.xml, instructs the application to use the Struts validator plug-in.

(good code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String email;
...

public RegistrationForm() {

super();

}

public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {...}

// getter and setter methods for private variables
...

}

The plug-in tag of the Struts configuration XML file includes the name of the validator plug-in to be used and includes a set-property tag to instruct the application to use the file, validator-rules.xml, for default validation rules and the file, validation.XML, for custom validation.

(good code)

Example Language: XML

<struts-config>

<form-beans>

<form-bean name="RegistrationForm" type="RegistrationForm"/>

</form-beans>

...


<plug-in className="org.apache.struts.validator.ValidatorPlugIn">

<set-property

property="pathnames"
value="/WEB-INF/validator-rules.xml,/WEB-INF/validation.xml"/>

</plug-in>

</struts-config>

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	722	OWASP Top Ten 2004 Category A1 - Unvalidated Input
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1406	Comprehensive Categorization: Improper Input Validation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Plug-in Framework Not In Use

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Potential_Mitigations
2013-07-17	CWE Content Team	MITRE
2013-07-17	updated Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2021-07-20	CWE Content Team	MITRE
2021-07-20	updated Potential_Mitigations
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 107

View customized information:

Description

An unused validation form indicates that validation logic is not up-to-date.

Extended Description

It is easy for developers to forget to update validation logic when they remove or rename action form mappings. One indication that validation logic is not being properly maintained is the presence of an unused validation form.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Quality Degradation

Potential Mitigations

Phase: Implementation

Remove the unused Validation Form from the validation.xml file.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1164	Irrelevant Code

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation
Operation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

In the following example the class RegistrationForm is a Struts framework ActionForm Bean that will maintain user input data from a registration webpage for an online business site. The user will enter registration data and, through the Struts framework, the RegistrationForm bean will maintain the user data in the form fields using the private member variables. The RegistrationForm class uses the Struts validation capability by extending the ValidatorForm class and including the validation for the form fields within the validator XML file, validator.xml.

(bad code)

Example Language: Java

public class RegistrationForm extends org.apache.struts.validator.ValidatorForm {

// private variables for registration form
private String name;
private String address;
private String city;
private String state;
private String zipcode;
// no longer using the phone form field

// private String phone;
private String email;

public RegistrationForm() {

super();

}

// getter and setter methods for private variables
...

}

(bad code)

Example Language: XML

<form-validation>

</field>
<field property="address" depends="required">

</field>
<field property="city" depends="required">

</field>
<field property="state" depends="required,mask">

<var-name>mask</var-name>
<var-value>[a-zA-Z]{2}</var-value>

</var>

</field>
<field property="zipcode" depends="required,mask">

<var-name>mask</var-name>
<var-value>\d{5}</var-value>

</var>

</field>
<field property="phone" depends="required,mask">

<var-name>mask</var-name>
<var-value>^([0-9]{3})(-)([0-9]{4}|[0-9]{4})$</var-value>

</var>

</field>
<field property="email" depends="required,email">

</field>

</form>

</formset>

</form-validation>

However, the validator XML file, validator.xml, for the RegistrationForm class includes the validation form for the user input form field "phone" that is no longer used by the input form and the RegistrationForm class. Any validation forms that are no longer required should be removed from the validator XML file, validator.xml.

The existence of unused forms may be an indication to attackers that this code is out of date or poorly maintained.

Weakness Ordinalities

Ordinality	Description
Resultant	(where the weakness is typically related to the presence of some other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Unused Validation Form

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Taxonomy_Mappings, Weakness_Ordinalities
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 108

View customized information:

Description

Every Action Form must have a corresponding validation form.

Extended Description

If a Struts Action Form Mapping specifies a form, it must have a validation form defined under the Struts Validator.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Other If an action form mapping does not have a validation form defined, it may be vulnerable to a number of attacks that rely on unchecked input. Unchecked input is the root cause of some of today's worst and most common software security problems. Cross-site scripting, SQL injection, and process control vulnerabilities all stem from incomplete or absent input validation.
Confidentiality Integrity Availability Other	Technical Impact: Other Although J2EE applications are not generally susceptible to memory corruption attacks, if a J2EE application interfaces with native code that does not perform array bounds checking, an attacker may be able to use an input validation mistake in the J2EE application to launch a buffer overflow attack.

Potential Mitigations

Phase: Implementation

Strategy: Input Validation

Map every Action Form to a corresponding validation form.

An action or a form may perform validation in other ways, but the Struts Validator provides an excellent way to verify that all input receives at least a basic level of validation. Without this approach, it is difficult, and often impossible, to establish with a high level of confidence that all input is validated.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1173	Improper Use of Validation Framework

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1406	Comprehensive Categorization: Improper Input Validation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Unvalidated Action Form
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Common_Consequences, Description, Other_Notes
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Common_Consequences, Other_Notes
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Other_Notes
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Other_Notes, Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 109

View customized information:

Description

Automatic filtering via a Struts bean has been turned off, which disables the Struts Validator and custom validation logic. This exposes the application to other weaknesses related to insufficient input validation.

Common Consequences

Scope	Impact	Likelihood
Access Control	Technical Impact: Bypass Protection Mechanism

Potential Mitigations

Phase: Implementation

Ensure that an action form mapping enables validation. Set the validate field to true.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	1173	Improper Use of Validation Framework

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

This mapping defines an action for a download form:

(bad code)

Example Language: XML

This mapping has disabled validation. Disabling validation exposes this action to numerous types of attacks.

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	722	OWASP Top Ten 2004 Category A1 - Unvalidated Input
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1406	Comprehensive Categorization: Improper Input Validation

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Other

The Action Form mapping in the demonstrative example disables the form's validate() method. The Struts bean: write tag automatically encodes special HTML characters, replacing a < with "<" and a > with ">". This action can be disabled by specifying filter="false" as an attribute of the tag to disable specified JSP pages. However, being disabled makes these pages susceptible to cross-site scripting attacks. An attacker may be able to insert malicious scripts as user input to write to these JSP pages.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Validator Turned Off
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Other_Notes
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2013-07-17	CWE Content Team	MITRE
2013-07-17	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 110

View customized information:

Description

Validation fields that do not appear in forms they are associated with indicate that the validation logic is out of date.

Extended Description

It is easy for developers to forget to update validation logic when they make changes to an ActionForm class. One indication that validation logic is not being properly maintained is inconsistencies between the action form and the validation form.

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Other It is critically important that validation logic be maintained and kept in sync with the rest of the application. Unchecked input is the root cause of some of today's worst and most common software security problems. Cross-site scripting, SQL injection, and process control vulnerabilities all stem from incomplete or absent input validation.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	1164	Irrelevant Code

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Implementation
Operation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

This example shows an inconsistency between an action form and a validation form. with a third field.

This first block of code shows an action form that has two fields, startDate and endDate.

(bad code)

Example Language: Java

public class DateRangeForm extends ValidatorForm {

String startDate, endDate;

public void setStartDate(String startDate) {

this.startDate = startDate;

}

public void setEndDate(String endDate) {

this.endDate = endDate;

}

This second block of related code shows a validation form with a third field: scale. The presence of the third field suggests that DateRangeForm was modified without taking validation into account.

(bad code)

Example Language: XML

</field>
<field property="endDate" depends="date">

</field>
<field property="scale" depends="integer">

</field>

</form>

Weakness Ordinalities

Ordinality	Description
Primary	(where the weakness exists independent of other weaknesses)

Detection Methods

Automated Static Analysis

To find the issue in the implementation, manual checks or automated static analysis could be applied to the XML configuration files.

Effectiveness: Moderate

Manual Static Analysis

To find the issue in the implementation, manual checks or automated static analysis could be applied to the XML configuration files.

Effectiveness: Moderate

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	990	SFP Secondary Cluster: Tainted Input to Command
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1412	Comprehensive Categorization: Poor Coding Practices

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Struts: Validator Without Form Field
Software Fault Patterns	SFP24		Tainted input to command

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2008-11-24	CWE Content Team	MITRE
2008-11-24	updated Common_Consequences, Description, Other_Notes
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Causal_Nature, Demonstrative_Examples, Detection_Factors, Potential_Mitigations, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2022-04-28	CWE Content Team	MITRE
2022-04-28	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes

Weakness ID: 248

View customized information:

Description

An exception is thrown from a function, but it is not caught.

Extended Description

When an exception is not caught, it may cause the program to crash or expose sensitive information.

Common Consequences

Scope	Impact	Likelihood
Availability Confidentiality	Technical Impact: DoS: Crash, Exit, or Restart; Read Application Data An uncaught exception could cause the system to be placed in a state that could lead to a crash, exposure of sensitive information or other unintended behaviors.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	755	Improper Handling of Exceptional Conditions
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	705	Incorrect Control Flow Scoping
ParentOf	Variant - a weakness that is linked to a certain type of product, typically involving a specific language or technology. More specific than a Base weakness. Variant level weaknesses typically describe issues in terms of 3 to 5 of the following dimensions: behavior, property, technology, language, and resource.	600	Uncaught Exception in Servlet

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	389	Error Conditions, Return Values, Status Codes

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	703	Improper Check or Handling of Exceptional Conditions

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Pillar - a weakness that is the most abstract type of weakness and represents a theme for all class/base/variant weaknesses related to it. A Pillar is different from a Category as a Pillar is still technically a type of weakness that describes a mistake, while a Category represents a common characteristic used to group related things.	703	Improper Check or Handling of Exceptional Conditions

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

C++ (Undetermined Prevalence)

Java (Undetermined Prevalence)

C# (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following example attempts to resolve a hostname.

(bad code)

Example Language: Java

protected void doPost (HttpServletRequest req, HttpServletResponse res) throws IOException {

String ip = req.getRemoteAddr();
InetAddress addr = InetAddress.getByName(ip);
...
out.println("hello " + addr.getHostName());

}

A DNS lookup failure will cause the Servlet to throw an exception.

Example 2

The _alloca() function allocates memory on the stack. If an allocation request is too large for the available stack space, _alloca() throws an exception. If the exception is not caught, the program will crash, potentially enabling a denial of service attack. _alloca() has been deprecated as of Microsoft Visual Studio 2005(R). It has been replaced with the more secure _alloca_s().

Example 3

EnterCriticalSection() can raise an exception, potentially causing the program to crash. Under operating systems prior to Windows 2000, the EnterCriticalSection() function can raise an exception in low memory situations. If the exception is not caught, the program will crash, potentially enabling a denial of service attack.

Observed Examples

Reference	Description
CVE-2023-41151	SDK for OPC Unified Architecture (OPC UA) server has uncaught exception when a socket is blocked for writing but the server tries to send an error
CVE-2023-21087	Java code in a smartphone OS can encounter a "boot loop" due to an uncaught exception

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	227	7PK - API Abuse
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	730	OWASP Top Ten 2004 Category A9 - Denial of Service
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	962	SFP Secondary Cluster: Unchecked Status Condition
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1141	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 07. Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1181	SEI CERT Perl Coding Standard - Guidelines 03. Expressions (EXP)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Often Misused: Exception Handling
The CERT Oracle Secure Coding Standard for Java (2011)	ERR05-J		Do not let checked exceptions escape from a finally block
The CERT Oracle Secure Coding Standard for Java (2011)	ERR06-J		Do not throw undeclared checked exceptions
SEI CERT Perl Coding Standard	EXP31-PL	Exact	Do not suppress or ignore exceptions
Software Fault Patterns	SFP4		Unchecked Status Condition

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-08-15		Veracode
2008-08-15	Suggested OWASP Top Ten 2004 mapping
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Applicable_Platforms, Relationships, Taxonomy_Mappings
2008-09-24	CWE Content Team	MITRE
2008-09-24	Removed C from Applicable_Platforms
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Applicable_Platforms
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Description, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Demonstrative_Examples, Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Related_Attack_Patterns
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes, Relationships
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Observed_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-01-30	Often Misused: Exception Handling

Weakness ID: 567

View customized information:

Description

The product does not properly synchronize shared data, such as static variables across threads, which can lead to undefined behavior and unpredictable data changes.

Extended Description

Within servlets, shared static variables are not protected from concurrent access, but servlets are multithreaded. This is a typical programming mistake in J2EE applications, since the multithreading is handled by the framework. When a shared variable can be influenced by an attacker, one thread could wind up modifying the variable to contain data that is not valid for a different thread that is also using the data within the variable.

Note that this weakness is not unique to servlets.

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity Availability	Technical Impact: Read Application Data; Modify Application Data; DoS: Instability; DoS: Crash, Exit, or Restart If the shared variable contains sensitive data, it may be manipulated or displayed in another user session. If this data is used to control the application, its value can be manipulated to cause the application to crash or perform poorly.

Potential Mitigations

Phase: Implementation

Remove the use of static variables used between servlets. If this cannot be avoided, use synchronized access for these variables.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	820	Missing Synchronization
CanPrecede	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	488	Exposure of Data Element to Wrong Session

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code implements a basic counter for how many times the page has been accesed.

(bad code)

Example Language: Java

public static class Counter extends HttpServlet {

static int count = 0;
protected void doGet(HttpServletRequest in, HttpServletResponse out)
throws ServletException, IOException {

out.setContentType("text/plain");
PrintWriter p = out.getWriter();
count++;
p.println(count + " hits so far!");

}

Consider when two separate threads, Thread A and Thread B, concurrently handle two different requests:

Assume this is the first occurrence of doGet, so the value of count is 0.
doGet() is called within Thread A.
The execution of doGet() in Thread A continues to the point AFTER the value of the count variable is read, then incremented, but BEFORE it is saved back to count. At this stage, the incremented value is 1, but the value of count is 0.
doGet() is called within Thread B, and due to a higher thread priority, Thread B progresses to the point where the count variable is accessed (where it is still 0), incremented, and saved. After the save, count is 1.
Thread A continues. It saves the intermediate, incremented value to the count variable - but the incremented value is 1, so count is "re-saved" to 1.

At this point, both Thread A and Thread B print that one hit has been seen, even though two separate requests have been processed. The value of count should be 2, not 1.

While this example does not have any real serious implications, if the shared variable in question is used for resource tracking, then resource consumption could occur. Other scenarios exist.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	852	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 9 - Visibility and Atomicity (VNA)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	986	SFP Secondary Cluster: Missing Lock
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1142	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 08. Visibility and Atomicity (VNA)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	VNA00-J	Ensure visibility when accessing shared primitive variables
The CERT Oracle Secure Coding Standard for Java (2011)	VNA02-J	Ensure that compound operations on shared variables are atomic
Software Fault Patterns	SFP19	Missing Lock

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-25	Forced Deadlock

Content History

Submissions
Submission Date	Submitter	Organization
2006-12-15 (CWE Draft 5, 2006-12-15)	CWE Community
2006-12-15 (CWE Draft 5, 2006-12-15)	Submitted by members of the CWE community to extend early CWE versions
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Other_Notes
2010-12-09	CWE Content Team	MITRE
2010-12-09	Made name and description more specific to match the essence of the rest of the entry.
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Description, Name, Other_Notes, Potential_Mitigations, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2013-07-17	CWE Content Team	MITRE
2013-07-17	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Applicable_Platforms
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships, Time_of_Introduction
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2010-12-13	Unsynchronized Access to Shared Data

Weakness ID: 470

View customized information:

Description

The product uses external input with reflection to select which classes or code to use, but it does not sufficiently prevent the input from selecting improper classes or code.

Extended Description

If the product uses external inputs to determine which class to instantiate or which method to invoke, then an attacker could supply values to select unexpected classes or methods. If this occurs, then the attacker could create control flow paths that were not intended by the developer. These paths could bypass authentication or access control checks, or otherwise cause the product to behave in an unexpected manner. This situation becomes a doomsday scenario if the attacker can upload files into a location that appears on the product's classpath (CWE-427) or add new entries to the product's classpath (CWE-426). Under either of these conditions, the attacker can use reflection to introduce new, malicious behavior into the product.

Alternate Terms

Reflection Injection

Common Consequences

Scope	Impact	Likelihood
Integrity Confidentiality Availability Other	Technical Impact: Execute Unauthorized Code or Commands; Alter Execution Logic The attacker might be able to execute code that is not directly accessible to the attacker. Alternately, the attacker could call unexpected code in the wrong place or the wrong time, possibly modifying critical system state.
Availability Other	Technical Impact: DoS: Crash, Exit, or Restart; Other The attacker might be able to use reflection to call the wrong code, possibly with unexpected arguments that violate the API (CWE-227). This could cause the product to exit or hang.
Confidentiality	Technical Impact: Read Application Data By causing the wrong code to be invoked, the attacker might be able to trigger a runtime error that leaks sensitive information in the error message, such as CWE-536.

Potential Mitigations

Phase: Architecture and Design

Refactor your code to avoid using reflection.

Phase: Architecture and Design

Do not use user-controlled inputs to select and load classes or code.

Phase: Implementation

Apply strict input validation by using allowlists or indirect selection to ensure that the user is only selecting allowable classes or code.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	610	Externally Controlled Reference to a Resource in Another Sphere
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	913	Improper Control of Dynamically-Managed Code Resources

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	399	Resource Management Errors

Relevant to the view "Weaknesses for Simplified Mapping of Published Vulnerabilities" (CWE-1003)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	913	Improper Control of Dynamically-Managed Code Resources

Relevant to the view "Seven Pernicious Kingdoms" (CWE-700)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	20	Improper Input Validation

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

PHP (Undetermined Prevalence)

Class: Interpreted (Sometimes Prevalent)

Demonstrative Examples

Example 1

A common reason that programmers use the reflection API is to implement their own command dispatcher. The following example shows a command dispatcher that does not use reflection:

(good code)

Example Language: Java

String ctl = request.getParameter("ctl");
Worker ao = null;
if (ctl.equals("Add")) {

ao = new AddCommand();

}
else if (ctl.equals("Modify")) {

ao = new ModifyCommand();

}
else {

throw new UnknownActionError();

}
ao.doAction(request);

A programmer might refactor this code to use reflection as follows:

(bad code)

Example Language: Java

String ctl = request.getParameter("ctl");
Class cmdClass = Class.forName(ctl + "Command");
Worker ao = (Worker) cmdClass.newInstance();
ao.doAction(request);

The refactoring initially appears to offer a number of advantages. There are fewer lines of code, the if/else blocks have been entirely eliminated, and it is now possible to add new command types without modifying the command dispatcher. However, the refactoring allows an attacker to instantiate any object that implements the Worker interface. If the command dispatcher is still responsible for access control, then whenever programmers create a new class that implements the Worker interface, they must remember to modify the dispatcher's access control code. If they do not modify the access control code, then some Worker classes will not have any access control.

One way to address this access control problem is to make the Worker object responsible for performing the access control check. An example of the re-refactored code follows:

(bad code)

Example Language: Java

String ctl = request.getParameter("ctl");
Class cmdClass = Class.forName(ctl + "Command");
Worker ao = (Worker) cmdClass.newInstance();
ao.checkAccessControl(request);
ao.doAction(request);

Although this is an improvement, it encourages a decentralized approach to access control, which makes it easier for programmers to make access control mistakes. This code also highlights another security problem with using reflection to build a command dispatcher. An attacker can invoke the default constructor for any kind of object. In fact, the attacker is not even constrained to objects that implement the Worker interface; the default constructor for any object in the system can be invoked. If the object does not implement the Worker interface, a ClassCastException will be thrown before the assignment to ao, but if the constructor performs operations that work in the attacker's favor, the damage will already have been done. Although this scenario is relatively benign in simple products, in larger products where complexity grows exponentially it is not unreasonable that an attacker could find a constructor to leverage as part of an attack.

Observed Examples

Reference	Description
CVE-2018-1000613	Cryptography API uses unsafe reflection when deserializing a private key
CVE-2004-2331	Database system allows attackers to bypass sandbox restrictions by using the Reflection API.

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	859	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 16 - Platform Security (SEC)
MemberOf	View - a subset of CWE entries that provides a way of examining CWE content. The two main view structures are Slices (flat lists) and Graphs (containing relationships between entries).	884	CWE Cross-section
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	991	SFP Secondary Cluster: Tainted Input to Environment
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1347	OWASP Top Ten 2021 Category A03:2021 - Injection
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1368	ICS Dependencies (& Architecture): External Digital Systems
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1415	Comprehensive Categorization: Resource Control

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Unsafe Reflection
The CERT Oracle Secure Coding Standard for Java (2011)	SEC06-J		Do not use reflection to increase accessibility of classes, methods, or fields

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-138	Reflection Injection

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-08-01		KDM Analytics
2008-08-01	added/updated white box definitions
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Relationships, Other_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Applicable_Platforms, Demonstrative_Examples, Description, Other_Notes
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Observed_Examples, Potential_Mitigations
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples, Name
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Alternate_Terms, Relationships
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated White_Box_Definitions
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References, Relationships
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Potential_Mitigations
2021-10-28	CWE Content Team	MITRE
2021-10-28	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Common_Consequences, Demonstrative_Examples, Description, Related_Attack_Patterns, Relationships
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2023-10-26	CWE Content Team	MITRE
2023-10-26	updated Observed_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Unsafe Reflection

2009-05-27	Use of Externally-Controlled Input to Select Classes or Code (aka 'Unsafe Reflection')

Weakness ID: 492

View customized information:

Description

Inner classes are translated into classes that are accessible at package scope and may expose code that the programmer intended to keep private to attackers.

Extended Description

Inner classes quietly introduce several security concerns because of the way they are translated into Java bytecode. In Java source code, it appears that an inner class can be declared to be accessible only by the enclosing class, but Java bytecode has no concept of an inner class, so the compiler must transform an inner class declaration into a peer class with package level access to the original outer class. More insidiously, since an inner class can access private fields in its enclosing class, once an inner class becomes a peer class in bytecode, the compiler converts private fields accessed by the inner class into protected fields.

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data "Inner Classes" data confidentiality aspects can often be overcome.

Potential Mitigations

Phase: Implementation

Using sealed classes protects object-oriented encapsulation paradigms and therefore protects code from being extended in unforeseen ways.

Phase: Implementation

Inner Classes do not provide security. Warning: Never reduce the security of the object from an outer class, going to an inner class. If an outer class is final or private, ensure that its inner class is private as well.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	668	Exposure of Resource to Wrong Sphere

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

The following Java Applet code mistakenly makes use of an inner class.

(bad code)

Example Language: Java

public final class urlTool extends Applet {

private final class urlHelper {

...

}
...

}

Example 2

The following example shows a basic use of inner classes. The class OuterClass contains the private member inner class InnerClass. The private inner class InnerClass includes the method concat that accesses the private member variables of the class OuterClass to output the value of one of the private member variables of the class OuterClass and returns a string that is a concatenation of one of the private member variables of the class OuterClass, the separator input parameter of the method and the private member variable of the class InnerClass.

(bad code)

Example Language: Java

public class OuterClass {

// private member variables of OuterClass
private String memberOne;
private String memberTwo;

// constructor of OuterClass
public OuterClass(String varOne, String varTwo) {

this.memberOne = varOne;
this.memberTwo = varTwo;

}

// InnerClass is a member inner class of OuterClass
private class InnerClass {

private String innerMemberOne;

public InnerClass(String innerVarOne) {

this.innerMemberOne = innerVarOne;

}

public String concat(String separator) {

// InnerClass has access to private member variables of OuterClass
System.out.println("Value of memberOne is: " + memberOne);
return OuterClass.this.memberTwo + separator + this.innerMemberOne;

}

Although this is an acceptable use of inner classes it demonstrates one of the weaknesses of inner classes that inner classes have complete access to all member variables and methods of the enclosing class even those that are declared private and protected. When inner classes are compiled and translated into Java bytecode the JVM treats the inner class as a peer class with package level access to the enclosing class.

To avoid this weakness of inner classes, consider using either static inner classes, local inner classes, or anonymous inner classes.

The following Java example demonstrates the use of static inner classes using the previous example. The inner class InnerClass is declared using the static modifier that signifies that InnerClass is a static member of the enclosing class OuterClass. By declaring an inner class as a static member of the enclosing class, the inner class can only access other static members and methods of the enclosing class and prevents the inner class from accessing nonstatic member variables and methods of the enclosing class. In this case the inner class InnerClass can only access the static member variable memberTwo of the enclosing class OuterClass but cannot access the nonstatic member variable memberOne.

(good code)

Example Language: Java

public class OuterClass {

// private member variables of OuterClass
private String memberOne;
private static String memberTwo;

// constructor of OuterClass
public OuterClass(String varOne, String varTwo) {

this.memberOne = varOne;
this.memberTwo = varTwo;

}

// InnerClass is a static inner class of OuterClass
private static class InnerClass {

private String innerMemberOne;

public InnerClass(String innerVarOne) {

this.innerMemberOne = innerVarOne;

}
public String concat(String separator) {

// InnerClass only has access to static member variables of OuterClass
return memberTwo + separator + this.innerMemberOne;

}

The only limitation with using a static inner class is that as a static member of the enclosing class the inner class does not have a reference to instances of the enclosing class. For many situations this may not be ideal. An alternative is to use a local inner class or an anonymous inner class as shown in the next examples.

Example 3

In the following example the BankAccount class contains the private member inner class InterestAdder that adds interest to the bank account balance. The start method of the BankAccount class creates an object of the inner class InterestAdder, the InterestAdder inner class implements the ActionListener interface with the method actionPerformed. A Timer object created within the start method of the BankAccount class invokes the actionPerformed method of the InterestAdder class every 30 days to add the interest to the bank account balance based on the interest rate passed to the start method as an input parameter. The inner class InterestAdder needs access to the private member variable balance of the BankAccount class in order to add the interest to the bank account balance.

However as demonstrated in the previous example, because InterestAdder is a non-static member inner class of the BankAccount class, InterestAdder also has access to the private member variables of the BankAccount class - including the sensitive data contained in the private member variables for the bank account owner's name, Social Security number, and the bank account number.

(bad code)

Example Language: Java

public class BankAccount {

// private member variables of BankAccount class
private String accountOwnerName;
private String accountOwnerSSN;
private int accountNumber;
private double balance;

// constructor for BankAccount class
public BankAccount(String accountOwnerName, String accountOwnerSSN,
int accountNumber, double initialBalance, int initialRate)
{

this.accountOwnerName = accountOwnerName;
this.accountOwnerSSN = accountOwnerSSN;
this.accountNumber = accountNumber;
this.balance = initialBalance;
this.start(initialRate);

}

// start method will add interest to balance every 30 days

// creates timer object and interest adding action listener object
public void start(double rate)
{

ActionListener adder = new InterestAdder(rate);
Timer t = new Timer(1000 * 3600 * 24 * 30, adder);
t.start();

}

// InterestAdder is an inner class of BankAccount class

// that implements the ActionListener interface
private class InterestAdder implements ActionListener
{

private double rate;

public InterestAdder(double aRate)
{

this.rate = aRate;

}

public void actionPerformed(ActionEvent event)
{

// update interest
double interest = BankAccount.this.balance * rate / 100;
BankAccount.this.balance += interest;

}

In the following example the InterestAdder class from the above example is declared locally within the start method of the BankAccount class. As a local inner class InterestAdder has its scope restricted to the method (or enclosing block) where it is declared, in this case only the start method has access to the inner class InterestAdder, no other classes including the enclosing class has knowledge of the inner class outside of the start method. This allows the inner class to access private member variables of the enclosing class but only within the scope of the enclosing method or block.

(good code)

Example Language: Java

public class BankAccount {

this.accountOwnerName = accountOwnerName;
this.accountOwnerSSN = accountOwnerSSN;
this.accountNumber = accountNumber;
this.balance = initialBalance;
this.start(initialRate);

}

// start method will add interest to balance every 30 days

// creates timer object and interest adding action listener object
public void start(final double rate)
{

// InterestAdder is a local inner class

// that implements the ActionListener interface
class InterestAdder implements ActionListener
{

public void actionPerformed(ActionEvent event)
{

// update interest
double interest = BankAccount.this.balance * rate / 100;
BankAccount.this.balance += interest;

}

}
ActionListener adder = new InterestAdder();
Timer t = new Timer(1000 * 3600 * 24 * 30, adder);
t.start();

}

A similar approach would be to use an anonymous inner class as demonstrated in the next example. An anonymous inner class is declared without a name and creates only a single instance of the inner class object. As in the previous example the anonymous inner class has its scope restricted to the start method of the BankAccount class.

(good code)

Example Language: Java

public class BankAccount {

this.accountOwnerName = accountOwnerName;
this.accountOwnerSSN = accountOwnerSSN;
this.accountNumber = accountNumber;
this.balance = initialBalance;
this.start(initialRate);

}

// start method will add interest to balance every 30 days

// creates timer object and interest adding action listener object
public void start(final double rate)
{

// anonymous inner class that implements the ActionListener interface
ActionListener adder = new ActionListener()
{

public void actionPerformed(ActionEvent event)
{

double interest = BankAccount.this.balance * rate / 100;
BankAccount.this.balance += interest;

}

};

Timer t = new Timer(1000 * 3600 * 24 * 30, adder);
t.start();

}

Example 4

In the following Java example a simple applet provides the capability for a user to input a URL into a text field and have the URL opened in a new browser window. The applet contains an inner class that is an action listener for the submit button, when the user clicks the submit button the inner class action listener's actionPerformed method will open the URL entered into the text field in a new browser window. As with the previous examples using inner classes in this manner creates a security risk by exposing private variables and methods. Inner classes create an additional security risk with applets as applets are executed on a remote machine through a web browser within the same JVM and therefore may run side-by-side with other potentially malicious code.

(bad code)

public class UrlToolApplet extends Applet {

// private member variables for applet components
private Label enterUrlLabel;
private TextField enterUrlTextField;
private Button submitButton;

// init method that adds components to applet

// and creates button listener object
public void init() {

setLayout(new FlowLayout());
enterUrlLabel = new Label("Enter URL: ");
enterUrlTextField = new TextField("", 20);
submitButton = new Button("Submit");
add(enterUrlLabel);
add(enterUrlTextField);
add(submitButton);
ActionListener submitButtonListener = new SubmitButtonListener();
submitButton.addActionListener(submitButtonListener);

}

// button listener inner class for UrlToolApplet class
private class SubmitButtonListener implements ActionListener {

public void actionPerformed(ActionEvent evt) {

if (evt.getSource() == submitButton) {

String urlString = enterUrlTextField.getText();
URL url = null;
try {

url = new URL(urlString);

} catch (MalformedURLException e) {

System.err.println("Malformed URL: " + urlString);

}
if (url != null) {

getAppletContext().showDocument(url);

}

As with the previous examples a solution to this problem would be to use a static inner class, a local inner class or an anonymous inner class. An alternative solution would be to have the applet implement the action listener rather than using it as an inner class as shown in the following example.

(good code)

Example Language: Java

public class UrlToolApplet extends Applet implements ActionListener {

}

// implementation of actionPerformed method of ActionListener interface
public void actionPerformed(ActionEvent evt) {

if (evt.getSource() == submitButton) {

String urlString = enterUrlTextField.getText();
URL url = null;
try {

url = new URL(urlString);

} catch (MalformedURLException e) {

System.err.println("Malformed URL: " + urlString);

}
if (url != null) {

getAppletContext().showDocument(url);

}

Detection Methods

Automated Static Analysis

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	485	7PK - Encapsulation
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	849	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 6 - Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	966	SFP Secondary Cluster: Other Exposures
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1139	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 05. Object Orientation (OBJ)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1403	Comprehensive Categorization: Exposed Resource

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Notes

Other

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
7 Pernicious Kingdoms		Mobile Code: Use of Inner Class
CLASP		Publicizing of private data when using inner classes
The CERT Oracle Secure Coding Standard for Java (2011)	OBJ08-J	Do not expose private members of an outer class from within a nested class

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Demonstrative_Examples
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Demonstrative_Examples, Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Description, References, Relationships
2022-10-13	CWE Content Team	MITRE
2022-10-13	updated Demonstrative_Examples
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Detection_Factors, Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Mobile Code: Use of Inner Class

Weakness ID: 395

View customized information:

Description

Catching NullPointerException should not be used as an alternative to programmatic checks to prevent dereferencing a null pointer.

Extended Description

Programmers typically catch NullPointerException under three circumstances:

The program contains a null pointer dereference. Catching the resulting exception was easier than fixing the underlying problem.
The program explicitly throws a NullPointerException to signal an error condition.
The code is part of a test harness that supplies unexpected input to the classes under test.

Of these three circumstances, only the last is acceptable.

Common Consequences

Scope	Impact	Likelihood
Availability	Technical Impact: DoS: Resource Consumption (CPU)

Potential Mitigations

Phases: Architecture and Design; Implementation

Do not extensively rely on catching exceptions (especially for validating user input) to handle errors. Handling exceptions can decrease the performance of an application.

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	755	Improper Handling of Exceptional Conditions
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	705	Incorrect Control Flow Scoping

Relevant to the view "Software Development" (CWE-699)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	389	Error Conditions, Return Values, Status Codes

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

Demonstrative Examples

Example 1

The following code mistakenly catches a NullPointerException.

(bad code)

Example Language: Java

try {

mysteryMethod();

} catch (NullPointerException npe) {
}

Detection Methods

Automated Static Analysis - Binary or Bytecode

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:

Bytecode Weakness Analysis - including disassembler + source code weakness analysis

Binary Weakness Analysis - including disassembler + source code weakness analysis

Effectiveness: SOAR Partial

Dynamic Analysis with Manual Results Interpretation

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:

Framework-based Fuzzer

Effectiveness: SOAR Partial

Manual Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Cost effective for partial coverage:

Manual Source Code Review (not inspections)

Effectiveness: SOAR Partial

Automated Static Analysis - Source Code

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Source code Weakness Analyzer

Context-configured Source Code Weakness Analyzer

Effectiveness: High

Architecture or Design Review

According to SOAR, the following detection techniques may be useful:

Highly cost effective:

Formal Methods / Correct-By-Construction

Cost effective for partial coverage:

Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	388	7PK - Errors
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	851	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 8 - Exceptional Behavior (ERR)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	962	SFP Secondary Cluster: Unchecked Status Condition
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1410	Comprehensive Categorization: Insufficient Control Flow Management

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Catching NullPointerException
The CERT Oracle Secure Coding Standard for Java (2011)	ERR08-J		Do not catch NullPointerException or any of its ancestors

References

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	7 Pernicious Kingdoms
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Demonstrative_Examples
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Other_Notes, Relationships
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Description, Other_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Detection_Factors, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated References
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
2024-02-29 (CWE 4.14, 2024-02-29)	CWE Content Team	MITRE
2024-02-29 (CWE 4.14, 2024-02-29)	updated Demonstrative_Examples
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Catch NullPointerException

Weakness ID: 543

View customized information:

Description

The product uses the singleton pattern when creating a resource within a multithreaded environment.

Extended Description

The use of a singleton pattern may not be thread-safe.

Common Consequences

Scope	Impact	Likelihood
Other Integrity	Technical Impact: Other; Modify Application Data

Potential Mitigations

Phase: Architecture and Design

Use the Thread-Specific Storage Pattern. See References.

Phase: Implementation

Do not use member fields to store information in the Servlet. In multithreading environments, storing user data in Servlet member fields introduces a data access race condition.

Phase: Implementation

Avoid using the double-checked locking pattern in language versions that cannot guarantee thread safety. This pattern may be used to avoid the overhead of a synchronized call, but in certain versions of Java (for example), this has been shown to be unsafe because it still introduces a race condition (CWE-209).

Effectiveness: Limited

Relationships

Relevant to the view "Research Concepts" (CWE-1000)

Nature	Type	ID	Name
ChildOf	Base - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.	820	Missing Synchronization

Relevant to the view "CISQ Quality Measures (2020)" (CWE-1305)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Relevant to the view "CISQ Data Protection Measures" (CWE-1340)

Nature	Type	ID	Name
ChildOf	Class - a weakness that is described in a very abstract fashion, typically independent of any specific language or technology. More specific than a Pillar Weakness, but more general than a Base Weakness. Class level weaknesses typically describe issues in terms of 1 or 2 of the following dimensions: behavior, property, and resource.	662	Improper Synchronization

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Java (Undetermined Prevalence)

C++ (Undetermined Prevalence)

Demonstrative Examples

Example 1

This method is part of a singleton pattern, yet the following singleton() pattern is not thread-safe. It is possible that the method will create two objects instead of only one.

(bad code)

Example Language: Java

private static NumberConverter singleton;
public static NumberConverter get_singleton() {

if (singleton == null) {

singleton = new NumberConverter();

}
return singleton;

}

Consider the following course of events:

Thread A enters the method, finds singleton to be null, begins the NumberConverter constructor, and then is swapped out of execution.
Thread B enters the method and finds that singleton remains null. This will happen if A was swapped out during the middle of the constructor, because the object reference is not set to point at the new object on the heap until the object is fully initialized.
Thread B continues and constructs another NumberConverter object and returns it while exiting the method.
Thread A continues, finishes constructing its NumberConverter object, and returns its version.

At this point, the threads have created and returned two different objects.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	861	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 18 - Miscellaneous (MSC)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	986	SFP Secondary Cluster: Missing Lock
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1401	Comprehensive Categorization: Concurrency

Vulnerability Mapping Notes

Usage: ALLOWED

(this CWE ID could be used to map to real-world vulnerabilities)

Reason: Acceptable-Use

Rationale:

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Comments:

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
The CERT Oracle Secure Coding Standard for Java (2011)	MSC07-J		Prevent multiple instantiations of singleton objects
Software Fault Patterns	SFP19		Missing Lock

References

[REF-474] Douglas C. Schmidt, Timothy H. Harrison and Nat Pryce. "Thread-Specifc Storage for C/C++". <http://www.cs.wustl.edu/~schmidt/PDF/TSS-pattern.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19 (CWE Draft 3, 2006-07-19)	Anonymous Tool Vendor (under NDA)
2006-07-19 (CWE Draft 3, 2006-07-19)
Modifications
Modification Date	Modifier	Organization
2008-07-01	Eric Dalci	Cigital
2008-07-01	updated Potential_Mitigations, Time_of_Introduction
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Taxonomy_Mappings
2010-09-27	CWE Content Team	MITRE
2010-09-27	updated Name
2010-12-13	CWE Content Team	MITRE
2010-12-13	updated Applicable_Platforms, Demonstrative_Examples, Description, Potential_Mitigations, References, Relationships, Taxonomy_Mappings
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Demonstrative_Examples
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Relationships, Taxonomy_Mappings
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships, Taxonomy_Mappings
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2023-01-31	CWE Content Team	MITRE
2023-01-31	updated Description
2023-04-27	CWE Content Team	MITRE
2023-04-27	updated Relationships
2023-06-29	CWE Content Team	MITRE
2023-06-29	updated Mapping_Notes
Previous Entry Names
Change Date	Previous Entry Name
2010-09-27	Use of Singleton Pattern in a Non-thread-safe Manner

Common Weakness Enumeration

CWE VIEW: Weaknesses in Software Written in Java

View Components

CWE-767: Access to Critical Private Variable via Public Method

Edit Custom Filter

CWE-582: Array Declared Public, Final, and Static

Edit Custom Filter

CWE-481: Assigning instead of Comparing

Edit Custom Filter

CWE-572: Call to Thread run() instead of start()

Edit Custom Filter

CWE-580: clone() Method Without super.clone()

Edit Custom Filter

CWE-498: Cloneable Class Containing Sensitive Information

Edit Custom Filter

CWE-486: Comparison of Classes by Name

Edit Custom Filter

CWE-595: Comparison of Object References Instead of Object Contents

Edit Custom Filter

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Edit Custom Filter

CWE-766: Critical Data Element Declared Public

Edit Custom Filter

CWE-493: Critical Public Variable Without Final Modifier

Edit Custom Filter

CWE-396: Declaration of Catch for Generic Exception

Edit Custom Filter

CWE-397: Declaration of Throws for Generic Exception

Edit Custom Filter

CWE-502: Deserialization of Untrusted Data

Edit Custom Filter

CWE-111: Direct Use of Unsafe JNI

Edit Custom Filter

CWE-609: Double-Checked Locking

Edit Custom Filter

CWE-462: Duplicate Key in Associative List (Alist)

Edit Custom Filter

CWE-575: EJB Bad Practices: Use of AWT Swing

Edit Custom Filter

CWE-578: EJB Bad Practices: Use of Class Loader

Edit Custom Filter

CWE-576: EJB Bad Practices: Use of Java I/O

Edit Custom Filter

CWE-577: EJB Bad Practices: Use of Sockets

Edit Custom Filter

CWE-574: EJB Bad Practices: Use of Synchronization Primitives

Edit Custom Filter

CWE-585: Empty Synchronized Block

Edit Custom Filter

CWE-586: Explicit Call to Finalize()

Edit Custom Filter

CWE-583: finalize() Method Declared Public

Edit Custom Filter

CWE-568: finalize() Method Without super.finalize()

Edit Custom Filter

CWE-209: Generation of Error Message Containing Sensitive Information

Edit Custom Filter

CWE-460: Improper Cleanup on Thrown Exception

Edit Custom Filter

CWE-95: Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')

Edit Custom Filter

CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine

Edit Custom Filter

CWE-917: Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

Edit Custom Filter

CWE-1335: Incorrect Bitwise Shift of Integer

Edit Custom Filter

CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations

Edit Custom Filter

CWE-192: Integer Coercion Error

Edit Custom Filter

CWE-191: Integer Underflow (Wrap or Wraparound)

Edit Custom Filter

CWE-245: J2EE Bad Practices: Direct Management of Connections

Edit Custom Filter

CWE-246: J2EE Bad Practices: Direct Use of Sockets

Edit Custom Filter

CWE-383: J2EE Bad Practices: Direct Use of Threads

Edit Custom Filter

CWE-579: J2EE Bad Practices: Non-serializable Object Stored in Session