CWE - VIEW SLICE: CWE-1081: Entries with Maintenance Notes (4.4)

CWE VIEW: Entries with Maintenance Notes

View ID: 1081

Type: Implicit

Status: Draft

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Objective

CWE entries in this view have maintenance notes. Maintenance notes are an indicator that an entry might change significantly in future versions. This view was created due to feedback from the CWE Board and participants in the CWE Compatibility Summit in March 2021.

Audience

Stakeholder	Description
Assessment Tool Vendors	Assessment vendors may use this view to anticipate future changes to CWE that will help them to better prepare customers for important changes in CWE.

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Membership

Nature	Type	ID	Name
HasMember	Category - a CWE entry that contains a set of other entries that share a common characteristic.	16	Configuration
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.	20	Improper Input Validation
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.	32	Path Traversal: '...' (Triple Dot)
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.	33	Path Traversal: '....' (Multiple Dot)
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.	73	External Control of File Name or Path
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.	91	XML Injection (aka Blind XPath Injection)
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.	99	Improper Control of Resource Identifiers ('Resource 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.	103	Struts: Incomplete validate() Method Definition
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.	114	Process Control
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.	131	Incorrect Calculation of Buffer Size
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.	159	Improper Handling of Invalid Use of Special Elements
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.	170	Improper Null Termination
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.	172	Encoding Error
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	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
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.	200	Exposure of Sensitive Information to an Unauthorized Actor
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.	202	Exposure of Sensitive Information Through Data Queries
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.	213	Exposure of Sensitive Information Due to Incompatible Policies
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.	226	Sensitive Information in Resource Not Removed Before Reuse
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.	228	Improper Handling of Syntactically Invalid Structure
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.	234	Failure to Handle Missing Parameter
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.	250	Execution with Unnecessary Privileges
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.	257	Storing Passwords in a Recoverable Format
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.	259	Use of Hard-coded Password
HasMember	Category - a CWE entry that contains a set of other entries that share a common characteristic.	264	Permissions, Privileges, and Access Controls
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.	267	Privilege Defined With Unsafe Actions
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.	269	Improper Privilege Management
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.	271	Privilege Dropping / Lowering Errors
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.	272	Least Privilege Violation
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.	274	Improper Handling of Insufficient Privileges
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.	280	Improper Handling of Insufficient Permissions or Privileges
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.	282	Improper Ownership Management
HasMember	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.	284	Improper Access Control
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.	286	Incorrect User Management
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.	300	Channel Accessible by Non-Endpoint
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.	301	Reflection Attack in an Authentication Protocol
HasMember	Category - a CWE entry that contains a set of other entries that share a common characteristic.	310	Cryptographic Issues
HasMember	Category - a CWE entry that contains a set of other entries that share a common characteristic.	320	Key Management Errors
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.	330	Use of Insufficiently Random Values
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.	339	Small Seed Space in PRNG
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.	345	Insufficient Verification of Data Authenticity
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.	346	Origin Validation Error
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.	350	Reliance on Reverse DNS Resolution for a Security-Critical Action
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.	359	Exposure of Private Personal Information to an Unauthorized Actor
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.	372	Incomplete Internal State Distinction
HasMember	Category - a CWE entry that contains a set of other entries that share a common characteristic.	387	Signal Errors
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.	391	Unchecked Error Condition
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.	400	Uncontrolled Resource Consumption
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.	428	Unquoted Search Path or Element
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.	441	Unintended Proxy or Intermediary ('Confused Deputy')
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.	446	UI Discrepancy for Security Feature
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.	451	User Interface (UI) Misrepresentation of Critical 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.	453	Insecure Default Variable Initialization
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.	466	Return of Pointer Value Outside of Expected Range
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	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.	538	Insertion of Sensitive Information into Externally-Accessible File or Directory
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.	600	Uncaught Exception in Servlet
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.	610	Externally Controlled Reference to a Resource in Another Sphere
HasMember	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
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.	640	Weak Password Recovery Mechanism for Forgotten Password
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.	654	Reliance on a Single Factor in a Security Decision
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.	662	Improper Synchronization
HasMember	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
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.	667	Improper Locking
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.	670	Always-Incorrect Control Flow Implementation
HasMember	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
HasMember	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.	707	Improper Neutralization
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.	708	Incorrect Ownership Assignment
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.	732	Incorrect Permission Assignment for Critical Resource
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.	761	Free of Pointer not at Start of Buffer
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.	763	Release of Invalid Pointer or Reference
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.	764	Multiple Locks of a Critical Resource
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.	765	Multiple Unlocks of a Critical Resource
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.	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.	772	Missing Release of Resource after Effective Lifetime
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.	780	Use of RSA Algorithm without OAEP
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.	784	Reliance on Cookies without Validation and Integrity Checking in a Security Decision
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.	785	Use of Path Manipulation Function without Maximum-sized Buffer
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.	820	Missing Synchronization
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.	821	Incorrect Synchronization
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.	822	Untrusted 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.	823	Use of Out-of-range Pointer Offset
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.	824	Access of Uninitialized Pointer
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.	825	Expired 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.	915	Improperly Controlled Modification of Dynamically-Determined Object Attributes
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.	922	Insecure Storage of Sensitive Information
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.	924	Improper Enforcement of Message Integrity During Transmission in a Communication Channel
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.	925	Improper Verification of Intent by Broadcast Receiver
HasMember	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
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.	1188	Insecure Default Initialization of Resource
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.	1191	Exposed Chip Debug and Test Interface With Insufficient or Missing Authorization
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.	1233	Improper Hardware Lock Protection for Security Sensitive Controls
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.	1240	Use of a Risky Cryptographic Primitive
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.	1244	Improper Access to Sensitive Information Using Debug and Test Interfaces
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.	1253	Incorrect Selection of Fuse Values
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.	1255	Comparison Logic is Vulnerable to Power Side-Channel Attacks
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.	1256	Hardware Features Enable Physical Attacks from Software
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.	1259	Improper Restriction of Security Token Assignment
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.	1260	Improper Handling of Overlap Between Protected Memory Ranges
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.	1263	Improper Physical Access Control
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.	1266	Improper Scrubbing of Sensitive Data from Decommissioned Device
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.	1268	Policy Privileges are not Assigned Consistently Between Control and Data Agents
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.	1271	Uninitialized Value on Reset for Registers Holding Security Settings
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.	1273	Device Unlock Credential Sharing
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.	1274	Insufficient Protections on the Volatile Memory Containing Boot Code
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.	1277	Firmware Not Updateable
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.	1278	Missing Protection Against Hardware Reverse Engineering Using Integrated Circuit (IC) Imaging Techniques
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.	1282	Assumed-Immutable Data is Stored in Writable Memory
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.	1283	Mutable Attestation or Measurement Reporting Data
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.	1284	Improper Validation of Specified Quantity in Input
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.	1285	Improper Validation of Specified Index, Position, or Offset in Input
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.	1286	Improper Validation of Syntactic Correctness of Input
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.	1287	Improper Validation of Specified Type of Input
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.	1288	Improper Validation of Consistency within Input
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.	1289	Improper Validation of Unsafe Equivalence in Input
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.	1294	Insecure Security Identifier Mechanism
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.	1296	Incorrect Chaining or Granularity of Debug Components
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.	1297	Unprotected Confidential Information on Device is Accessible by OSAT Vendors
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.	1300	Improper Protection Against Physical Side Channels
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.	1301	Insufficient or Incomplete Data Removal within Hardware Component
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.	1310	Missing Ability to Patch ROM Code
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.	1315	Improper Setting of Bus Controlling Capability in Fabric End-point
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.	1319	Improper Protection against Electromagnetic Fault Injection (EM-FI)
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.	1329	Reliance on Component That is Not Updateable
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.	1332	Insufficient Protection Against Instruction Skipping Via Fault Injection

View Metrics

	CWEs in this view		Total CWEs
Weaknesses	119	out of	918
Categories	5	out of	316
Views	2	out of	43
Total	126	out of	1277

Content History

Submissions
Submission Date	Submitter	Organization
2021-03-14	CWE Content Team	MITRE
2021-03-14

View Components

Weakness ID: 300

Abstraction: Class
Structure: Simple

Status: Draft

Presentation Filter:

Description

The product does not adequately verify the identity of actors at both ends of a communication channel, or does not adequately ensure the integrity of the channel, in a way that allows the channel to be accessed or influenced by an actor that is not an endpoint.

Extended Description

In order to establish secure communication between two parties, it is often important to adequately verify the identity of entities at each end of the communication channel. Inadequate or inconsistent verification may result in insufficient or incorrect identification of either communicating entity. This can have negative consequences such as misplaced trust in the entity at the other end of the channel. An attacker can leverage this by interposing between the communicating entities and masquerading as the original entity. In the absence of sufficient verification of identity, such an attacker can eavesdrop and potentially modify the communication between the original entities.

Alternate Terms

Man-in-the-Middle / MITM
Person-in-the-Middle / PiTM
Monkey-in-the-Middle
Monster-in-the-Middle
On-path attack
Interception attack

Relationships

The table(s) below 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.	923	Improper Restriction of Communication Channel to Intended Endpoints
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.	1324	Sensitive Information Accessible by Physical Probing of JTAG Interface
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.	602	Client-Side Enforcement of Server-Side Security
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.	603	Use of Client-Side Authentication

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.	1011	Authorize Actors

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
Architecture and Design	REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Applicable Platforms

The listings below show 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

Class: Language-Independent (Undetermined Prevalence)

Common Consequences

The table below 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
Confidentiality Integrity Access Control	Technical Impact: Read Application Data; Modify Application Data; Gain Privileges or Assume Identity An attacker could pose as one of the entities and read or possibly modify the communication.

Demonstrative Examples

Example 1

In the Java snippet below, data is sent over an unencrypted channel to a remote server.

(bad code)

Example Language: Java

Socket sock;
PrintWriter out;

try {

sock = new Socket(REMOTE_HOST, REMOTE_PORT);
out = new PrintWriter(echoSocket.getOutputStream(), true);

// Write data to remote host via socket output stream.
...

}

By eavesdropping on the communication channel or posing as the endpoint, an attacker would be able to read all of the transmitted data.

Observed Examples

Reference	Description
CVE-2014-1266	chain: incorrect "goto" in Apple SSL product bypasses certificate validation, allowing MITM attack (Apple "goto fail" bug). CWE-705 (Incorrect Control Flow Scoping) -> CWE-561 (Dead Code) -> CWE-295 (Improper Certificate Validation) -> CWE-393 (Return of Wrong Status Code) -> CWE-300 (Channel Accessible by Non-Endpoint).

Potential Mitigations

Phase: Implementation

Always fully authenticate both ends of any communications channel.

Phase: Architecture and Design

Adhere to the principle of complete mediation.

Phase: Implementation

A certificate binds an identity to a cryptographic key to authenticate a communicating party. Often, the certificate takes the encrypted form of the hash of the identity of the subject, the public key, and information such as time of issue or expiration using the issuer's private key. The certificate can be validated by deciphering the certificate with the issuer's public key. See also X.509 certificate signature chains and the PGP certification structure.

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.	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.	956	SFP Secondary Cluster: Channel Attack

Notes

Maintenance

The summary identifies multiple distinct possibilities, suggesting that this is a category that must be broken into more specific weaknesses.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
PLOVER		Man-in-the-middle (MITM)
WASC	32	Routing Detour
The CERT Oracle Secure Coding Standard for Java (2011)	SEC06-J	Do not rely on the default automatic signature verification provided by URLClassLoader and java.util.jar

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-466	Leveraging Active Man in the Middle Attacks to Bypass Same Origin Policy
CAPEC-57	Utilizing REST's Trust in the System Resource to Obtain Sensitive Data
CAPEC-589	DNS Blocking
CAPEC-590	IP Address Blocking
CAPEC-612	WiFi MAC Address Tracking
CAPEC-613	WiFi SSID Tracking
CAPEC-615	Evil Twin Wi-Fi Attack
CAPEC-662	Man in the Browser
CAPEC-94	Man in the Middle Attack

References

[REF-244] M. Bishop. "Computer Security: Art and Science". Addison-Wesley. 2003.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	PLOVER
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 Description, Maintenance_Notes, Relationships, Taxonomy_Mappings
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Name
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Taxonomy_Mappings
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, Relationships, Taxonomy_Mappings
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Common_Consequences, Related_Attack_Patterns, Relationships, Taxonomy_Mappings
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Observed_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Demonstrative_Examples, Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Applicable_Platforms, Modes_of_Introduction, 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 Related_Attack_Patterns
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Alternate_Terms, Name, Observed_Examples, Related_Attack_Patterns, Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Alternate_Terms, Related_Attack_Patterns
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Man-in-the-middle (MITM)

2009-05-27	Channel Accessible by Non-Endpoint (aka 'Man-in-the-Middle')

2020-02-24	Channel Accessible by Non-Endpoint ('Man-in-the-Middle')

Weakness ID: 1255

Abstraction: Base
Structure: Simple

Status: Draft

Presentation Filter:

Description

A device's real time power consumption may be monitored during security token evaluation and the information gleaned may be used to determine the value of the reference token.

Extended Description

The power consumed by a device may be instrumented and monitored in real time. If the algorithm for evaluating security tokens is not sufficiently robust, the power consumption may vary by token entry comparison against the reference value. Further, if retries are unlimited, the power difference between a "good" entry and a "bad" entry may be observed and used to determine whether each entry itself is correct thereby allowing unauthorized parties to calculate the reference value.

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.	205	Observable Behavioral Discrepancy

Relevant to the view "Hardware Design" (CWE-1194)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1206	Power, Clock, and Reset Concerns
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.	1259	Improper Restriction of Security Token Assignment

Modes Of Introduction

Phase	Note
Architecture and Design	The design of the algorithm itself may intrinsically allow the power side channel attack to be effective
Implementation	Even if the design is not robust, implementation may mitigate a design which would otherwise allow exploitation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Operating Systems

Class: OS-Independent (Undetermined Prevalence)

Architectures

Class: Architecture-Independent (Undetermined Prevalence)

Technologies

Class: Technology-Independent (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity Availability Access Control Accountability Authentication Authorization Non-Repudiation	Technical Impact: Modify Memory; Read Memory; Read Files or Directories; Modify Files or Directories; Execute Unauthorized Code or Commands; Gain Privileges or Assume Identity; Bypass Protection Mechanism; Read Application Data; Modify Application Data; Hide Activities As compromising a security token may result in complete system control, the impacts are relatively universal

Demonstrative Examples

Example 1

Consider an example hardware module that checks a user-provided password (or PIN) to grant access to a user. The user-provided password is compared against a stored value byte-by-byte.

(bad code)

Example Language: Other

static nonvolatile password_tries = NUM_RETRIES;
do
  while (password_tries == 0) ; // Hang here if no more password tries
  password_ok = 0;
  for (i = 0; i < NUM_PW_DIGITS; i++)
    if (GetPasswordByte() == stored_password([i])
      password_ok |= 1; // Power consumption is different here
    else
      password_ok |= 0; // than from here
  end
  if (password_ok > 0)
    password_tries = NUM_RETRIES;
    break_to_Ok_to_proceed
  password_tries--;
while (true)
// Password OK

Since the algorithm uses a different number of 1's and 0's for password validation, a different amount of power is consumed for the good byte versus the bad byte comparison. Using this information, an attacker may be able to guess the correct password for that byte-by-byte iteration with several repeated attempts by stopping the password evaluation before it completes.

(good code)

Among various options for mitigating the string comparison is obscuring the power comsumption by having opposing bit flips during bit operations. Note that in this example, the initial change of the bit values could still provide power indication depending upon the hardware itself. This possibility needs to be measured for verification.
static nonvolatile password_tries = NUM_RETRIES;
do
  while (password_tries == 0) ; // Hang here if no more password tries
  password_tries--; // Put retry code here to catch partial retries
  password_ok = 0;
  for (i = 0; i < NUM_PW_DIGITS; i++)
    if (GetPasswordByte() == stored_password([i])
      password_ok |= 0x10; // Power consumption here
    else
      password_ok |= 0x01; // is now the same here
  end
  if ((password_ok & 1) == 0)
    password_tries = NUM_RETRIES;
    break_to_Ok_to_proceed
while (true)
// Password OK

(good code)

An alternative to the previous example is simply comparing the whole password simultaneously.

static nonvolatile password_tries = NUM_RETRIES;
do
  while (password_tries == 0) ; // Hang here if no more password tries
  password_tries--; // Put retry code here to catch partial retries
  for (i = 0; i < NUM_PW_DIGITS; i++)
    stored_password([i] = GetPasswordByte();
  end
  if (stored_password == saved_password)
    password_tries = NUM_RETRIES;
    break_to_Ok_to_proceed
while (true)
// Password OK

Since comparison is done atomically, there is no indication which bytes fail forcing the attacker to brute force the whole password at once. Note that other mitigations may exist such as masking - causing a large current draw to mask individual bit flips.

Potential Mitigations

Phase: Architecture and Design

The design phase must consider each check of a security token against a standard and the amount of power consumed during the check of a good token versus a bad token. The alternative is an all at once check where a retry counter is incremented PRIOR to the check.

Phase: Implementation

If the architecture is unable prevent the attack, using filtering components may reduce the ability to implement an attack, however, consideration must be given to the physical removal of the filter elements.

Functional Areas

Power

Notes

Maintenance

As of CWE 4.3, CWE-1300 and CWE-1255 are being investigated for potential duplication or overlap, since they are both related to physical side channels but have different ChildOf/MemberOf relationships in views 1000 and 1194.

Content History

Submissions
Submission Date	Submitter	Organization
2020-05-29	CWE Content Team	MITRE
2020-05-29
Modifications
Modification Date	Modifier	Organization
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Functional_Areas, Maintenance_Notes, Relationships

Weakness ID: 362

Abstraction: Class
Structure: Simple

Status: Draft

Presentation Filter:

Description

The program 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 program; 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 program.

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

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

Nature	Type	ID	Name
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)

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 program(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).

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-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-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

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.

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	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
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)

Notes

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.

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.

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. <http://www.ddj.com/cpp/184403766>.

[REF-350] Steven Devijver. "Thread-safe webapps using Spring". <http://www.javalobby.org/articles/thread-safe/index.jsp>.

[REF-351] David Wheeler. "Prevent race conditions". 2007-10-04. <http://www.ibm.com/developerworks/library/l-sprace.html>.

[REF-352] Matt Bishop. "Race Conditions, Files, and Security Flaws; or the Tortoise and the Hare Redux". 1995-09. <http://www.cs.ucdavis.edu/research/tech-reports/1995/CSE-95-9.pdf>.

[REF-353] David Wheeler. "Secure Programming for Linux and Unix HOWTO". 2003-03-03. <http://www.dwheeler.com/secure-programs/Secure-Programs-HOWTO/avoid-race.html>.

[REF-354] Blake Watts. "Discovering and Exploiting Named Pipe Security Flaws for Fun and Profit". 2002-04. <http://www.blakewatts.com/namedpipepaper.html>.

[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. <http://developer.apple.com/documentation/Security/Conceptual/SecureCodingGuide/Articles/RaceConditions.html>.

[REF-357] Johannes Ullrich. "Top 25 Series - Rank 25 - Race Conditions". SANS Software Security Institute. 2010-03-26. <http://blogs.sans.org/appsecstreetfighter/2010/03/26/top-25-series-rank-25-race-conditions/>.

[REF-76] Sean Barnum and Michael Gegick. "Least Privilege". 2005-09-14. <https://buildsecurityin.us-cert.gov/daisy/bsi/articles/knowledge/principles/351.html>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	PLOVER
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
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Race Conditions

2010-12-13	Race Condition

Weakness ID: 502

Abstraction: Base
Structure: Simple

Status: Draft

Presentation Filter:

Description

The application 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.

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)

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.

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.

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.

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).	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

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. <http://www.slideshare.net/codewhitesec/exploiting-deserialization-vulnerabilities-in-java-54707478>.

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

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

[REF-464] Heine Deelstra. "Unserializing user-supplied data, a bad idea". 2010-08-25. <http://heine.familiedeelstra.com/security/unserialize>.

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

[REF-466] Nadia Alramli. "Why Python Pickle is Insecure". 2009-09-09. <http://nadiana.com/python-pickle-insecure>.

[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://www.slideshare.net/frohoff1/deserialize-my-shorts-or-how-i-learned-to-start-worrying-and-hate-java-object-deserialization>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	CLASP
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

Weakness ID: 172

Abstraction: Class
Structure: Simple

Status: Draft

Presentation Filter:

Description

The software does not properly encode or decode the data, resulting in unexpected 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.	707	Improper Neutralization
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.	173	Improper Handling of Alternate Encoding
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.	174	Double Decoding of the Same Data
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.	175	Improper Handling of Mixed Encoding
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.	176	Improper Handling of Unicode Encoding
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.	177	Improper Handling of URL Encoding (Hex Encoding)
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.	22	Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
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.	41	Improper Resolution of Path Equivalence

Modes Of Introduction

Phase	Note
Implementation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Integrity	Technical Impact: Unexpected State

Potential Mitigations

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

Strategy: Output Encoding

While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments. The most conservative approach is to escape or filter all characters that do not pass an extremely strict allowlist (such as everything that is not alphanumeric or white space). If some special characters are still needed, such as white space, wrap each argument in quotes after the escaping/filtering step. Be careful of argument injection (CWE-88).

Phase: Implementation

Strategy: Input Validation

Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	992	SFP Secondary Cluster: Faulty Input Transformation

Notes

Maintenance

This is more like a category than a weakness.

Maintenance

Many other types of encodings should be listed in this category.

Relationship

Partially overlaps path traversal and equivalence weaknesses.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Encoding Error

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-120	Double Encoding
CAPEC-267	Leverage Alternate Encoding
CAPEC-3	Using Leading 'Ghost' Character Sequences to Bypass Input Filters
CAPEC-52	Embedding NULL Bytes
CAPEC-53	Postfix, Null Terminate, and Backslash
CAPEC-64	Using Slashes and URL Encoding Combined to Bypass Validation Logic
CAPEC-71	Using Unicode Encoding to Bypass Validation Logic
CAPEC-72	URL Encoding
CAPEC-78	Using Escaped Slashes in Alternate Encoding
CAPEC-80	Using UTF-8 Encoding to Bypass Validation Logic

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	PLOVER
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 Maintenance_Notes, Relationships, Relationship_Notes, Taxonomy_Mappings
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated 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 Potential_Mitigations
2011-06-01	CWE Content Team	MITRE
2011-06-01	updated Common_Consequences, Description
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Common_Consequences
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Related_Attack_Patterns, 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 Potential_Mitigations
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Applicable_Platforms
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Related_Attack_Patterns
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Relationships
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

Weakness ID: 250

Abstraction: Base
Structure: Simple

Status: Draft

Presentation Filter:

Description

The software performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.

Extended Description

New weaknesses can be exposed because running with extra privileges, such as root or Administrator, can disable the normal security checks being performed by the operating system or surrounding environment. Other pre-existing weaknesses can turn into security vulnerabilities if they occur while operating at raised privileges.

Privilege management functions can behave in some less-than-obvious ways, and they have different quirks on different platforms. These inconsistencies are particularly pronounced if you are transitioning from one non-root user to another. Signal handlers and spawned processes run at the privilege of the owning process, so if a process is running as root when a signal fires or a sub-process is executed, the signal handler or sub-process will operate with root privileges.

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.	269	Improper Privilege Management
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.	657	Violation of Secure Design Principles

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

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
Implementation	REALIZATION: This weakness is caused during implementation of an architectural security tactic.
Installation
Architecture and Design	If an application has this design problem, then it can be easier for the developer to make implementation-related errors such as CWE-271 (Privilege Dropping / Lowering Errors). In addition, the consequences of Privilege Chaining (CWE-268) can become more severe.
Operation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Technologies

Class: Mobile (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity Availability Access Control	Technical Impact: Gain Privileges or Assume Identity; Execute Unauthorized Code or Commands; Read Application Data; DoS: Crash, Exit, or Restart An attacker will be able to gain access to any resources that are allowed by the extra privileges. Common results include executing code, disabling services, and reading restricted data.

Likelihood Of Exploit

Medium

Demonstrative Examples

Example 1

This code temporarily raises the program's privileges to allow creation of a new user folder.

(bad code)

Example Language: Python

def makeNewUserDir(username):

if invalidUsername(username):

#avoid CWE-22 and CWE-78
print('Usernames cannot contain invalid characters')
return False

try:

raisePrivileges()
os.mkdir('/home/' + username)
lowerPrivileges()

except OSError:

print('Unable to create new user directory for user:' + username)
return False

return True

While the program only raises its privilege level to create the folder and immediately lowers it again, if the call to os.mkdir() throws an exception, the call to lowerPrivileges() will not occur. As a result, the program is indefinitely operating in a raised privilege state, possibly allowing further exploitation to occur.

Example 2

The following code calls chroot() to restrict the application to a subset of the filesystem below APP_HOME in order to prevent an attacker from using the program to gain unauthorized access to files located elsewhere. The code then opens a file specified by the user and processes the contents of the file.

(bad code)

Example Language: C

chroot(APP_HOME);
chdir("/");
FILE* data = fopen(argv[1], "r+");
...

Constraining the process inside the application's home directory before opening any files is a valuable security measure. However, the absence of a call to setuid() with some non-zero value means the application is continuing to operate with unnecessary root privileges. Any successful exploit carried out by an attacker against the application can now result in a privilege escalation attack because any malicious operations will be performed with the privileges of the superuser. If the application drops to the privilege level of a non-root user, the potential for damage is substantially reduced.

Example 3

This application intends to use a user's location to determine the timezone the user is in:

(bad code)

Example Language: Java

locationClient = new LocationClient(this, this, this);
locationClient.connect();
Location userCurrLocation;
userCurrLocation = locationClient.getLastLocation();
setTimeZone(userCurrLocation);

This is unnecessary use of the location API, as this information is already available using the Android Time API. Always be sure there is not another way to obtain needed information before resorting to using the location API.

Example 4

This code uses location to determine the user's current US State location.

First the application must declare that it requires the ACCESS_FINE_LOCATION permission in the application's manifest.xml:

(bad code)

Example Language: XML

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

During execution, a call to getLastLocation() will return a location based on the application's location permissions. In this case the application has permission for the most accurate location possible:

(bad code)

Example Language: Java

locationClient = new LocationClient(this, this, this);
locationClient.connect();
Location userCurrLocation;
userCurrLocation = locationClient.getLastLocation();
deriveStateFromCoords(userCurrLocation);

While the application needs this information, it does not need to use the ACCESS_FINE_LOCATION permission, as the ACCESS_COARSE_LOCATION permission will be sufficient to identify which US state the user is in.

Observed Examples

Reference	Description
CVE-2007-4217	FTP client program on a certain OS runs with setuid privileges and has a buffer overflow. Most clients do not need extra privileges, so an overflow is not a vulnerability for those clients.
CVE-2008-1877	Program runs with privileges and calls another program with the same privileges, which allows read of arbitrary files.
CVE-2007-5159	OS incorrectly installs a program with setuid privileges, allowing users to gain privileges.
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-2008-0162	Program does not drop privileges before calling another program, allowing code execution.
CVE-2008-0368	setuid root program allows creation of arbitrary files through command line argument.
CVE-2007-3931	Installation script installs some programs as setuid when they shouldn't be.

Potential Mitigations

Phases: Architecture and Design; Operation

Strategy: Environment Hardening

Phase: Architecture and Design

Strategy: Separation of Privilege

Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code [REF-76]. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.

Phase: Architecture and Design

Strategy: Attack Surface Reduction

Phase: Implementation

Perform extensive input validation for any privileged code that must be exposed to the user and reject anything that does not fit your strict requirements.

Phase: Implementation

When dropping privileges, ensure that they have been dropped successfully to avoid CWE-273. As protection mechanisms in the environment get stronger, privilege-dropping calls may fail even if it seems like they would always succeed.

Phase: Implementation

If circumstances force you to run with extra privileges, then determine the minimum access level necessary. First identify the different permissions that the software and its users will need to perform their actions, such as file read and write permissions, network socket permissions, and so forth. Then explicitly allow those actions while denying all else [REF-76]. Perform extensive input validation and canonicalization to minimize the chances of introducing a separate vulnerability. This mitigation is much more prone to error than dropping the privileges in the first place.

Phases: Operation; System Configuration

Strategy: Environment Hardening

Ensure that the software runs properly under the Federal Desktop Core Configuration (FDCC) [REF-199] or an equivalent hardening configuration guide, which many organizations use to limit the attack surface and potential risk of deployed software.

Detection Methods

Manual Analysis

This weakness can be detected using tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session.

Note: These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.

Black Box

Use monitoring tools that examine the software's process as it interacts with the operating system and the network. This technique is useful in cases when source code is unavailable, if the software was not developed by you, or if you want to verify that the build phase did not introduce any new weaknesses. Examples include debuggers that directly attach to the running process; system-call tracing utilities such as truss (Solaris) and strace (Linux); system activity monitors such as FileMon, RegMon, Process Monitor, and other Sysinternals utilities (Windows); and sniffers and protocol analyzers that monitor network traffic.

Attach the monitor to the process and perform a login. Look for library functions and system calls that indicate when privileges are being raised or dropped. Look for accesses of resources that are restricted to normal users.

Note: Note that this technique is only useful for privilege issues related to system resources. It is not likely to detect application-level business rules that are related to privileges, such as if a blog system allows a user to delete a blog entry without first checking that the user has administrator privileges.

Automated Static Analysis - Binary or Bytecode

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

Highly cost effective:

Compare binary / bytecode to application permission manifest

Cost effective for partial coverage:

Bytecode Weakness Analysis - including disassembler + source code weakness analysis

Binary Weakness Analysis - including disassembler + source code weakness analysis

Effectiveness: High

Manual Static Analysis - Binary or Bytecode

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

Cost effective for partial coverage:

Binary / Bytecode disassembler - then use manual analysis for vulnerabilities & anomalies

Effectiveness: SOAR Partial

Dynamic Analysis with Automated Results Interpretation

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

Cost effective for partial coverage:

Host-based Vulnerability Scanners - Examine configuration for flaws, verifying that audit mechanisms work, ensure host configuration meets certain predefined criteria

Effectiveness: SOAR Partial

Dynamic Analysis with Manual Results Interpretation

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

Cost effective for partial coverage:

Host Application Interface Scanner

Effectiveness: SOAR Partial

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:

Cost effective for partial coverage:

Source code Weakness Analyzer

Context-configured Source Code Weakness Analyzer

Effectiveness: SOAR Partial

Automated Static Analysis

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

Cost effective for partial coverage:

Configuration Checker

Permission Manifest Analysis

Effectiveness: SOAR Partial

Architecture or Design Review

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

Highly cost effective:

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

Formal Methods / Correct-By-Construction

Cost effective for partial coverage:

Attack Modeling

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.	753	2009 Top 25 - Porous Defenses
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.	858	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 15 - Serialization (SER)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	866	2011 Top 25 - Porous Defenses
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.	901	SFP Primary Cluster: Privilege

Notes

Maintenance

CWE-271, CWE-272, and CWE-250 are all closely related and possibly overlapping. CWE-271 is probably better suited as a category. Both CWE-272 and CWE-250 are in active use by the community. The "least privilege" phrase has multiple interpretations.

Relationship

There is a close association with CWE-653 (Insufficient Separation of Privileges). CWE-653 is about providing separate components for each privilege; CWE-250 is about ensuring that each component has the least amount of privileges possible.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Often Misused: Privilege Management
The CERT Oracle Secure Coding Standard for Java (2011)	SER09-J		Minimize privileges before deserializing from a privilege context

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-104	Cross Zone Scripting
CAPEC-470	Expanding Control over the Operating System from the Database
CAPEC-69	Target Programs with Elevated Privileges

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-196] Jerome H. Saltzer and Michael D. Schroeder. "The Protection of Information in Computer Systems". Proceedings of the IEEE 63. 1975-09. <http://web.mit.edu/Saltzer/www/publications/protection/>.

[REF-76] Sean Barnum and Michael Gegick. "Least Privilege". 2005-09-14. <https://buildsecurityin.us-cert.gov/daisy/bsi/articles/knowledge/principles/351.html>.

[REF-7] Michael Howard and David LeBlanc. "Writing Secure Code". Chapter 7, "Running with Least Privilege" Page 207. 2nd Edition. Microsoft Press. 2002-12-04. <https://www.microsoftpressstore.com/store/writing-secure-code-9780735617223>.

[REF-199] NIST. "Federal Desktop Core Configuration". <http://nvd.nist.gov/fdcc/index.cfm>.

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 16: Executing Code With Too Much Privilege." Page 243. McGraw-Hill. 2010.

[REF-62] Mark Dowd, John McDonald and Justin Schuh. "The Art of Software Security Assessment". Chapter 9, "Privilege Vulnerabilities", Page 477. 1st Edition. Addison Wesley. 2006.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	7 Pernicious Kingdoms
2006-07-19
Modifications
Modification Date	Modifier	Organization
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Description, Modes_of_Introduction, Relationships, Other_Notes, Relationship_Notes, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description, Maintenance_Notes
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Common_Consequences, Description, Likelihood_of_Exploit, Maintenance_Notes, Name, Observed_Examples, Other_Notes, Potential_Mitigations, Relationships, Time_of_Introduction
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Potential_Mitigations
2009-05-27	CWE Content Team	MITRE
2009-05-27	updated Related_Attack_Patterns
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Detection_Factors, Potential_Mitigations, References
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Detection_Factors, Potential_Mitigations
2011-03-29	CWE Content Team	MITRE
2011-03-29	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 Demonstrative_Examples, Relationships
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Potential_Mitigations, References, Relationships
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated References, Related_Attack_Patterns, 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 Applicable_Platforms
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Demonstrative_Examples
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Detection_Factors
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Modes_of_Introduction, References, Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated References
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Taxonomy_Mappings
2019-09-19	CWE Content Team	MITRE
2019-09-19	updated Demonstrative_Examples
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Applicable_Platforms, Detection_Factors, Observed_Examples, References, Relationships, Type
Previous Entry Names
Change Date	Previous Entry Name
2008-01-30	Often Misused: Privilege Management

2009-01-12	Design Principle Violation: Failure to Use Least Privilege

Weakness ID: 825

Abstraction: Base
Structure: Simple

Status: Incomplete

Presentation Filter:

Description

The program dereferences a pointer that contains a location for memory that was previously valid, but is no longer valid.

Extended Description

When a program releases memory, but it maintains a pointer to that memory, then the memory might be re-allocated at a later time. If the original pointer is accessed to read or write data, then this could cause the program to read or modify data that is in use by a different function or process. Depending on how the newly-allocated memory is used, this could lead to a denial of service, information exposure, or code execution.

Alternate Terms

Dangling pointer

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.	672	Operation on a Resource after Expiration or Release
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.	119	Improper Restriction of Operations within the Bounds of a Memory Buffer
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
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.	416	Use After Free
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.	562	Return of Stack Variable Address
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.	125	Out-of-bounds Read
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.	787	Out-of-bounds Write

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 "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.	119	Improper Restriction of Operations within the Bounds of a Memory Buffer

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.	119	Improper Restriction of Operations within the Bounds of a Memory Buffer

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Memory If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.
Availability	Technical Impact: DoS: Crash, Exit, or Restart If the expired pointer references a memory location that is not accessible to the program, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity Confidentiality Availability	Technical Impact: Execute Unauthorized Code or Commands If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.

Demonstrative Examples

Example 1

The following code shows a simple example of a use after free error:

(bad code)

Example Language: C

char* ptr = (char*)malloc (SIZE);
if (err) {

abrt = 1;
free(ptr);

}
...
if (abrt) {

logError("operation aborted before commit", ptr);

}

When an error occurs, the pointer is immediately freed. However, this pointer is later incorrectly used in the logError function.

Example 2

The following code shows a simple example of a double free error:

(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 the previous 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-2008-5013	access of expired memory address leads to arbitrary code execution
CVE-2010-3257	stale pointer issue leads to denial of service and possibly other consequences
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-2007-1211	read of value at an offset into a structure after the offset is no longer valid

Potential Mitigations

Phase: Architecture and Design

Choose a language that provides automatic memory management.

Phase: Implementation

When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

Memberships

Nature	Type	ID	Name
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	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

Notes

Maintenance

There are close relationships between incorrect pointer dereferences and other weaknesses related to buffer operations. There may not be sufficient community agreement regarding these relationships. Further study is needed to determine when these relationships are chains, composites, perspective/layering, or other types of relationships. As of September 2010, most of the relationships are being captured as chains.

Research Gap

Under-studied and probably under-reported as of September 2010. This weakness has been reported in high-visibility software, but applied vulnerability researchers have only been investigating it since approximately 2008, and there are only a few public reports. Few reports identify weaknesses at such a low level, which makes it more difficult to find and study real-world code examples.

Terminology

Many weaknesses related to pointer dereferences fall under the general term of "memory corruption" or "memory safety." As of September 2010, there is no commonly-used terminology that covers the lower-level variants.

Content History

Submissions
Submission Date	Submitter	Organization
2010-09-22	CWE Content Team	MITRE
2010-09-22
Modifications
Modification Date	Modifier	Organization
2011-06-27	CWE Content Team	MITRE
2011-06-27	updated Demonstrative_Examples, Potential_Mitigations, Relationships
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Demonstrative_Examples, Relationships
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Alternate_Terms
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
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Observed_Examples

Weakness ID: 1191

Abstraction: Base
Structure: Simple

Status: Draft

Presentation Filter:

Description

The chip does not implement or does not correctly check whether users are authorized to access internal registers.

Extended Description

A device's internal information may be accessed through a scan chain of interconnected internal registers usually through a JTAG interface. The JTAG interface provides access to these registers in a serial fashion in the form of a scan chain for the purposes of debugging programs running on a device. Since almost all information contained within a device may be accessed over this interface, device manufacturers typically insert some form of authentication and authorization to prevent unintended use of this sensitive information. This mechanism is implemented in addition to on-chip protections that are already present. If this control is not implemented or not implemented properly a user may be able to bypass on-chip protection mechanisms through debug 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.	863	Incorrect Authorization
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.	1263	Improper Physical Access Control

Relevant to the view "Hardware Design" (CWE-1194)

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1207	Debug and Test Problems
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.	1299	Missing Protection Mechanism for Alternate Hardware Interface

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Operating Systems

Class: OS-Independent (Undetermined Prevalence)

Architectures

Class: Architecture-Independent (Undetermined Prevalence)

Technologies

Class: Technology-Independent (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data	High
Confidentiality	Technical Impact: Read Memory	High
Authorization	Technical Impact: Execute Unauthorized Code or Commands	High
Integrity	Technical Impact: Modify Memory	High
Integrity	Technical Impact: Modify Application Data	High
Access Control	Technical Impact: Bypass Protection Mechanism	High

Demonstrative Examples

Example 1

A home, WiFi-router device implements a login prompt which prevents an unauthorized user from issuing any commands on the device until appropriate credentials are provided. The credentials are protected on the device and are checked for strength against attack.

(bad code)

Example Language: Other

If the JTAG interface on this device is not hidden by the manufacturer, the interface may be identified using tools such as JTAGulator. If it is hidden but not disabled, it can be exposed by physically wiring to the board.

By issuing a halt command before the OS starts, the unauthorized user pauses the watchdog timer and prevents the router from restarting (once the watchdog timer would have expired). Having paused the router, an unauthorized user is able to execute code and inspect and modify data in the device even extracting all of the routers firmware. This allows the user to examine the router and potentially take over the router.

JTAG is useful to chip and device manufacturers during design, testing, and production and is included in nearly every product. Without proper authentication and authorization, the interface may allow tampering with a product.

(good code)

Example Language: Other

In order to prevent exposing the debugging interface, manufacturers might try to obfuscate JTAG interface or blow device internal fuses to disable the JTAG interface. Adding authentication and authorization to this interface makes use by unauthorized individuals much more difficult..

Observed Examples

Reference	Description
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

Potential Mitigations

Phase: Architecture and Design

Strategy: Separation of Privilege

Password checking logic should be resistant to timing attacks. Security-sensitive data stored in registers, such as keys, etc. should be cleared when entering debug mode.

Notes

Maintenance

This entry is still in development and will continue to see updates and content improvements.

Maintenance

As of CWE 4.3, CWE-1191 and CWE-1244 are being investigated for potential duplication or overlap, since they are both related to authorization of debug/test interfaces.

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-1	Accessing Functionality Not Properly Constrained by ACLs
CAPEC-180	Exploiting Incorrectly Configured Access Control Security Levels

References

[REF-1037] Kurt Rosenfeld and Ramesh Karri. "Attacks and Defenses for JTAG". 2010-02. <https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5406671>.

[REF-1043] Gopal Vishwakarma and Wonjun Lee. "Exploiting JTAG and Its Mitigation in IOT: A Survey". 2018-12-03. <https://www.mdpi.com/1999-5903/10/12/121/pdf>.

[REF-1084] Gopal Vishwakarma and Wonjun Lee. "JTAG Explained (finally!): Why “IoT”, Software Security Engineers, and Manufacturers Should Care". <https://www.mdpi.com/1999-5903/10/12/121/pdf >.

[REF-1085] Bob Molyneaux, Mark McDermott and Anil Sabbavarapu. "Design for Testability & Design for Debug". <http://users.ece.utexas.edu/~mcdermot/vlsi-2/Lecture_17.pdf>.

Content History

Submissions
Submission Date	Submitter	Organization
2019-10-15	Arun Kanuparthi, Hareesh Khattri, Parbati Kumar Manna, Narasimha Kumar V Mangipudi	Intel Corporation
2019-10-15
Modifications
Modification Date	Modifier	Organization
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Description, Name, References, Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Applicable_Platforms, Demonstrative_Examples, Description, Name, Potential_Mitigations, Related_Attack_Patterns, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Maintenance_Notes
Previous Entry Names
Change Date	Previous Entry Name
2020-02-26	Exposed Chip Debug Interface With Insufficient Access Control

2020-08-20	Exposed Chip Debug and or Test Interface With Insufficient Access Control

Weakness ID: 359

Abstraction: Base
Structure: Simple

Status: Incomplete

Presentation Filter:

Description

The product does not properly prevent a person's private, personal information from being accessed by actors who either (1) are not explicitly authorized to access the information or (2) do not have the implicit consent of the person about whom the information is collected.

Extended Description

There are many types of sensitive information that products must protect from attackers, including system data, communications, configuration, business secrets, intellectual property, and an individual's personal (private) information. Private personal information may include a password, phone number, geographic location, personal messages, credit card number, etc. Private information is important to consider whether the person is a user of the product, or part of a data set that is processed by the product. An exposure of private information does not necessarily prevent the product from working properly, and in fact the exposure might be intended by the developer, e.g. as part of data sharing with other organizations. However, the exposure of personal private information can still be undesirable or explicitly prohibited by law or regulation.

Some types of private information include:

Government identifiers, such as Social Security Numbers
Contact information, such as home addresses and telephone numbers
Geographic location - where the user is (or was)
Employment history
Financial data - such as credit card numbers, salary, bank accounts, and debts
Pictures, video, or audio
Behavioral patterns - such as web surfing history, when certain activities are performed, etc.
Relationships (and types of relationships) with others - family, friends, contacts, etc.
Communications - e-mail addresses, private messages, text messages, chat logs, etc.
Health - medical conditions, insurance status, prescription records
Account passwords and other credentials

Some of this information may be characterized as PII (Personally Identifiable Information), Protected Health Information (PHI), etc. Categories of private information may overlap or vary based on the intended usage or the policies and practices of a particular industry.

Sometimes data that is not labeled as private can have a privacy implication in a different context. For example, student identification numbers are usually not considered private because there is no explicit and publicly-available mapping to an individual student's personal information. However, if a school generates identification numbers based on student social security numbers, then the identification numbers should be considered private.

Alternate Terms

Privacy violation
Privacy leak
Privacy leakage

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.	200	Exposure of Sensitive Information to an Unauthorized Actor

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

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.	1011	Authorize Actors

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
Operation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Technologies

Class: Mobile (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data

Demonstrative Examples

Example 1

The following code contains a logging statement that tracks the contents of records added to a database by storing them in a log file. Among other values that are stored, the getPassword() function returns the user-supplied plaintext password associated with the account.

(bad code)

Example Language: C#

pass = GetPassword();
...
dbmsLog.WriteLine(id + ":" + pass + ":" + type + ":" + tstamp);

The code in the example above logs a plaintext password to the filesystem. Although many developers trust the filesystem as a safe storage location for data, it should not be trusted implicitly, particularly when privacy is a concern.

Example 2

This code uses location to determine the user's current US State location.

First the application must declare that it requires the ACCESS_FINE_LOCATION permission in the application's manifest.xml:

(bad code)

Example Language: XML

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

(bad code)

Example Language: Java

Example 3

In 2004, an employee at AOL sold approximately 92 million private customer e-mail addresses to a spammer marketing an offshore gambling web site [REF-338]. In response to such high-profile exploits, the collection and management of private data is becoming increasingly regulated.

Potential Mitigations

Phase: Requirements

Identify and consult all relevant regulations for personal privacy. An organization may be required to comply with certain federal and state regulations, depending on its location, the type of business it conducts, and the nature of any private data it handles. Regulations may include Safe Harbor Privacy Framework [REF-340], Gramm-Leach Bliley Act (GLBA) [REF-341], Health Insurance Portability and Accountability Act (HIPAA) [REF-342], General Data Protection Regulation (GDPR) [REF-1047], California Consumer Privacy Act (CCPA) [REF-1048], and others.

Phase: Architecture and Design

Carefully evaluate how secure design may interfere with privacy, and vice versa. Security and privacy concerns often seem to compete with each other. From a security perspective, all important operations should be recorded so that any anomalous activity can later be identified. However, when private data is involved, this practice can in fact create risk. Although there are many ways in which private data can be handled unsafely, a common risk stems from misplaced trust. Programmers often trust the operating environment in which a program runs, and therefore believe that it is acceptable store private information on the file system, in the registry, or in other locally-controlled resources. However, even if access to certain resources is restricted, this does not guarantee that the individuals who do have access can be trusted.

Detection Methods

Architecture or Design Review

Private personal data can enter a program in a variety of ways:

Directly from the user in the form of a password or personal information

Accessed from a database or other data store by the application

Indirectly from a partner or other third party

If the data is written to an external location - such as the console, file system, or network - a privacy violation may occur.

Effectiveness: High

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	254	7PK - Security Features
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	857	The CERT Oracle Secure Coding Standard for Java (2011) Chapter 14 - Input Output (FIO)
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	975	SFP Secondary Cluster: Architecture
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1029	OWASP Top Ten 2017 Category A3 - Sensitive Data Exposure
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1147	SEI CERT Oracle Secure Coding Standard for Java - Guidelines 13. Input Output (FIO)
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

Notes

Maintenance

This entry overlaps many other entries that are not organized around the kind of sensitive information that is exposed. However, because privacy is treated with such importance due to regulations and other factors, and it may be useful for weakness-finding tools to highlight capabilities that detect personal private information instead of system information, it is not clear whether - and how - this entry should be deprecated.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Privacy Violation
The CERT Oracle Secure Coding Standard for Java (2011)	FIO13-J		Do not log sensitive information outside a trust boundary

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-464	Evercookie
CAPEC-467	Cross Site Identification
CAPEC-508	Shoulder Surfing

References

[REF-338] J. Oates. "AOL man pleads guilty to selling 92m email addies". The Register. 2005. <http://www.theregister.co.uk/2005/02/07/aol_email_theft/>.

[REF-339] NIST. "Guide to Protecting the Confidentiality of Personally Identifiable Information (SP 800-122)". 2010-04. <http://csrc.nist.gov/publications/nistpubs/800-122/sp800-122.pdf>.

[REF-340] U.S. Department of Commerce. "Safe Harbor Privacy Framework". <http://www.export.gov/safeharbor/>.

[REF-341] Federal Trade Commission. "Financial Privacy: The Gramm-Leach Bliley Act (GLBA)". <http://www.ftc.gov/privacy/glbact/index.html>.

[REF-342] U.S. Department of Human Services. "Health Insurance Portability and Accountability Act (HIPAA)". <http://www.hhs.gov/ocr/hipaa/>.

[REF-343] Government of the State of California. "California SB-1386". 2002. <http://info.sen.ca.gov/pub/01-02/bill/sen/sb_1351-1400/sb_1386_bill_20020926_chaptered.html>.

[REF-267] Information Technology Laboratory, National Institute of Standards and Technology. "SECURITY REQUIREMENTS FOR CRYPTOGRAPHIC MODULES". 2001-05-25. <http://csrc.nist.gov/publications/fips/fips140-2/fips1402.pdf>.

[REF-172] Chris Wysopal. "Mobile App Top 10 List". 2010-12-13. <http://www.veracode.com/blog/2010/12/mobile-app-top-10-list/>.

[REF-1047] Wikipedia. "General Data Protection Regulation". <https://en.wikipedia.org/wiki/General_Data_Protection_Regulation>.

[REF-1048] State of California Department of Justice, Office of the Attorney General. "California Consumer Privacy Act (CCPA)". <https://oag.ca.gov/privacy/ccpa>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	7 Pernicious Kingdoms
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 Other_Notes
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Other_Notes, References
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Other_Notes, References
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, Relationships, Taxonomy_Mappings
2011-09-13	CWE Content Team	MITRE
2011-09-13	updated Other_Notes, References
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Related_Attack_Patterns, Relationships, Taxonomy_Mappings
2013-02-21	CWE Content Team	MITRE
2013-02-21	updated Applicable_Platforms, References
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Alternate_Terms, Demonstrative_Examples, Description, Name, Other_Notes, References
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Modes_of_Introduction, 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 Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Alternate_Terms, Applicable_Platforms, Demonstrative_Examples, Description, Detection_Factors, Maintenance_Notes, Name, Potential_Mitigations, References, Relationships, Type
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Related_Attack_Patterns
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated References
Previous Entry Names
Change Date	Previous Entry Name
2014-02-18	Privacy Violation

2020-02-24	Exposure of Private Information ('Privacy Violation')

Weakness ID: 200

Abstraction: Class
Structure: Simple

Status: Draft

Presentation Filter:

Description

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Extended Description

There are many different kinds of mistakes that introduce information exposures. The severity of the error can range widely, depending on the context in which the product operates, the type of sensitive information that is revealed, and the benefits it may provide to an attacker. Some kinds of sensitive information include:

private, personal information, such as personal messages, financial data, health records, geographic location, or contact details
system status and environment, such as the operating system and installed packages
business secrets and intellectual property
network status and configuration
the product's own code or internal state
metadata, e.g. logging of connections or message headers
indirect information, such as a discrepancy between two internal operations that can be observed by an outsider

Information might be sensitive to different parties, each of which may have their own expectations for whether the information should be protected. These parties include:

the product's own users
people or organizations whose information is created or used by the product, even if they are not direct product users
the product's administrators, including the admins of the system(s) and/or networks on which the product operates
the developer

Information exposures can occur in different ways:

the code explicitly inserts sensitive information into resources or messages that are intentionally made accessible to unauthorized actors, but should not contain the information - i.e., the information should have been "scrubbed" or "sanitized"
a different weakness or mistake indirectly inserts the sensitive information into resources, such as a web script error revealing the full system path of the program.
the code manages resources that intentionally contain sensitive information, but the resources are unintentionally made accessible to unauthorized actors. In this case, the information exposure is resultant - i.e., a different weakness enabled the access to the information in the first place.

It is common practice to describe any loss of confidentiality as an "information exposure," but this can lead to overuse of CWE-200 in CWE mapping. From the CWE perspective, loss of confidentiality is a technical impact that can arise from dozens of different weaknesses, such as insecure file permissions or out-of-bounds read. CWE-200 and its lower-level descendants are intended to cover the mistakes that occur in behaviors that explicitly manage, store, transfer, or cleanse sensitive information.

Alternate Terms

Information Disclosure:

This term is frequently used in vulnerability advisories to describe a consequence or technical impact, for any vulnerability that has a loss of confidentiality. Often, CWE-200 can be misused to represent the loss of confidentiality, even when the mistake - i.e., the weakness - is not directly related to the mishandling of the information itself, such as an out-of-bounds read that accesses sensitive memory contents; here, the out-of-bounds read is the primary weakness, not the disclosure of the memory. In addition, this phrase is also used frequently in policies and legal documents, but it does not refer to any disclosure of security-relevant information.

Information Leak:

This is a frequently used term, however the "leak" term has multiple uses within security. In some cases it deals with the accidental exposure of information from a different weakness, but in other cases (such as "memory leak"), this deals with improper tracking of resources, which can lead to exhaustion. As a result, CWE is actively avoiding usage of the "leak" term.

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	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.	201	Insertion of Sensitive Information Into Sent Data
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.	203	Observable Discrepancy
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.	209	Generation of 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.	213	Exposure of Sensitive Information Due to Incompatible Policies
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.	215	Insertion of Sensitive Information Into Debugging Code
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.	359	Exposure of Private Personal 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.	497	Exposure of Sensitive System Information to an Unauthorized Control Sphere
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.	538	Insertion of Sensitive Information into Externally-Accessible File or Directory
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.	1243	Sensitive Non-Volatile Information Not Protected During Debug
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.	1258	Exposure of Sensitive System Information Due to Uncleared Debug 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.	1273	Device Unlock Credential Sharing
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.	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.	498	Cloneable Class Containing Sensitive 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.	499	Serializable Class Containing Sensitive Data
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.	1272	Sensitive Information Uncleared Before Debug/Power State Transition

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

Nature	Type	ID	Name
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.	203	Observable Discrepancy
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.	209	Generation of 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.	532	Insertion of Sensitive Information into Log File

Modes Of Introduction

Phase	Note
Architecture and Design
Implementation

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Technologies

Class: Mobile (Undetermined Prevalence)

Common Consequences

Scope	Impact	Likelihood
Confidentiality	Technical Impact: Read Application Data

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

The following code checks validity of the supplied username and password and notifies the user of a successful or failed login.

(bad code)

Example Language: Perl

my $username=param('username');
my $password=param('password');

if (IsValidUsername($username) == 1)
{

if (IsValidPassword($username, $password) == 1)
{

print "Login Successful";

}
else
{

print "Login Failed - incorrect password";

}

}
else
{

print "Login Failed - unknown username";

}

In the above code, there are different messages for when an incorrect username is supplied, versus when the username is correct but the password is wrong. This difference enables a potential attacker to understand the state of the login function, and could allow an attacker to discover a valid username by trying different values until the incorrect password message is returned. In essence, this makes it easier for an attacker to obtain half of the necessary authentication credentials.

While this type of information may be helpful to a user, it is also useful to a potential attacker. In the above example, the message for both failed cases should be the same, such as:

(result)

"Login Failed - incorrect username or password"

Example 2

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

(bad code)

Example Language: Java

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

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.

Example 4

This code stores location information about the current user:

(bad code)

Example Language: Java

locationClient = new LocationClient(this, this, this);
locationClient.connect();
currentUser.setLocation(locationClient.getLastLocation());
...

catch (Exception e) {

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Sorry, this application has experienced an error.");
AlertDialog alert = builder.create();
alert.show();
Log.e("ExampleActivity", "Caught exception: " + e + " While on User:" + User.toString());

}

When the application encounters an exception it will write the user object to the log. Because the user object contains location information, the user's location is also written to the log.

Example 5

The following is an actual MySQL error statement:

(result)

Example Language: SQL

Warning: mysql_pconnect(): Access denied for user: 'root@localhost' (Using password: N1nj4) in /usr/local/www/wi-data/includes/database.inc on line 4

The error clearly exposes the database credentials.

Example 6

This code displays some information on a web page.

(bad code)

Example Language: JSP

Social Security Number: <%= ssn %></br>Credit Card Number: <%= ccn %>

The code displays a user's credit card and social security numbers, even though they aren't absolutely necessary.

Example 7

The following program changes its behavior based on a debug flag.

(bad code)

Example Language: JSP

<% if (Boolean.getBoolean("debugEnabled")) {

%>
User account number: <%= acctNo %>
<%
} %>

The code writes sensitive debug information to the client browser if the "debugEnabled" flag is set to true .

Example 8

This code uses location to determine the user's current US State location.

First the application must declare that it requires the ACCESS_FINE_LOCATION permission in the application's manifest.xml:

(bad code)

Example Language: XML

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

(bad code)

Example Language: Java

Observed Examples

Reference	Description
CVE-2001-1483	Enumeration of valid usernames based on inconsistent responses
CVE-2001-1528	Account number enumeration via inconsistent responses.
CVE-2004-2150	User enumeration via discrepancies in error messages.
CVE-2005-1205	Telnet protocol allows servers to obtain sensitive environment information from clients.
CVE-2002-1725	Script calls phpinfo(), revealing system configuration to web user
CVE-2002-0515	Product sets a different TTL when a port is being filtered than when it is not being filtered, which allows remote attackers to identify filtered ports by comparing TTLs.
CVE-2004-0778	Version control system allows remote attackers to determine the existence of arbitrary files and directories via the -X command for an alternate history file, which causes different error messages to be returned.
CVE-2000-1117	Virtual machine allows malicious web site operators to determine the existence of files on the client by measuring delays in the execution of the getSystemResource method.
CVE-2003-0190	Product immediately sends an error message when a user does not exist, which allows remote attackers to determine valid usernames via a timing attack.
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-2007-1409	Direct request to library file in web application triggers pathname leak in error message.
CVE-2005-0603	Malformed regexp syntax leads to information exposure in error message.
CVE-2004-2268	Password exposed in debug information.
CVE-2003-1078	FTP client with debug option enabled shows password to the screen.

Potential Mitigations

Phase: Architecture and Design

Strategy: Separation of Privilege

Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.

Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

Weakness Ordinalities

Ordinality	Description
Primary	Developers may insert sensitive information that they do not believe, or they might forget to remove the sensitive information after it has been processed (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)
Resultant	Separate mistakes or weaknesses could inadvertently make the sensitive information available to an attacker, such as in a detailed error message that can be read by an unauthorized party (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 - 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

Inter-application Flow Analysis

Effectiveness: SOAR Partial

Dynamic Analysis with Automated Results Interpretation

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

Highly cost effective:

Web Application Scanner

Web Services Scanner

Database Scanners

Effectiveness: High

Dynamic Analysis with Manual Results Interpretation

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

Cost effective for partial coverage:

Fuzz Tester

Framework-based Fuzzer

Automated Monitored Execution

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

Effectiveness: SOAR Partial

Manual Static Analysis - Source Code

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

Highly cost effective:

Manual Source Code Review (not inspections)

Effectiveness: High

Automated Static Analysis - Source Code

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

Highly cost effective:

Context-configured Source Code Weakness Analyzer

Cost effective for partial coverage:

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:

Attack Modeling

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.	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.	963	SFP Secondary Cluster: Exposed Data
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
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	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

Notes

Maintenance

As a result of mapping analysis in the 2020 Top 25, this weakness is under review, since it is frequently misused in mapping to cover many problems that lead to loss of confidentiality. See Extended Decription and Alternate Terms.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
PLOVER			Information Leak (information disclosure)
OWASP Top Ten 2007	A6	CWE More Specific	Information Leakage and Improper Error Handling
WASC	13		Information Leakage

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-116	Excavation
CAPEC-13	Subverting Environment Variable Values
CAPEC-169	Footprinting
CAPEC-22	Exploiting Trust in Client
CAPEC-224	Fingerprinting
CAPEC-285	ICMP Echo Request Ping
CAPEC-287	TCP SYN Scan
CAPEC-290	Enumerate Mail Exchange (MX) Records
CAPEC-291	DNS Zone Transfers
CAPEC-292	Host Discovery
CAPEC-293	Traceroute Route Enumeration
CAPEC-294	ICMP Address Mask Request
CAPEC-295	Timestamp Request
CAPEC-296	ICMP Information Request
CAPEC-297	TCP ACK Ping
CAPEC-298	UDP Ping
CAPEC-299	TCP SYN Ping
CAPEC-300	Port Scanning
CAPEC-301	TCP Connect Scan
CAPEC-302	TCP FIN Scan
CAPEC-303	TCP Xmas Scan
CAPEC-304	TCP Null Scan
CAPEC-305	TCP ACK Scan
CAPEC-306	TCP Window Scan
CAPEC-307	TCP RPC Scan
CAPEC-308	UDP Scan
CAPEC-309	Network Topology Mapping
CAPEC-310	Scanning for Vulnerable Software
CAPEC-312	Active OS Fingerprinting
CAPEC-313	Passive OS Fingerprinting
CAPEC-317	IP ID Sequencing Probe
CAPEC-318	IP 'ID' Echoed Byte-Order Probe
CAPEC-319	IP (DF) 'Don't Fragment Bit' Echoing Probe
CAPEC-320	TCP Timestamp Probe
CAPEC-321	TCP Sequence Number Probe
CAPEC-322	TCP (ISN) Greatest Common Divisor Probe
CAPEC-323	TCP (ISN) Counter Rate Probe
CAPEC-324	TCP (ISN) Sequence Predictability Probe
CAPEC-325	TCP Congestion Control Flag (ECN) Probe
CAPEC-326	TCP Initial Window Size Probe
CAPEC-327	TCP Options Probe
CAPEC-328	TCP 'RST' Flag Checksum Probe
CAPEC-329	ICMP Error Message Quoting Probe
CAPEC-330	ICMP Error Message Echoing Integrity Probe
CAPEC-472	Browser Fingerprinting
CAPEC-497	File Discovery
CAPEC-508	Shoulder Surfing
CAPEC-573	Process Footprinting
CAPEC-574	Services Footprinting
CAPEC-575	Account Footprinting
CAPEC-576	Group Permission Footprinting
CAPEC-577	Owner Footprinting
CAPEC-59	Session Credential Falsification through Prediction
CAPEC-60	Reusing Session IDs (aka Session Replay)
CAPEC-616	Establish Rogue Location
CAPEC-643	Identify Shared Files/Directories on System
CAPEC-646	Peripheral Footprinting
CAPEC-651	Eavesdropping
CAPEC-79	Using Slashes in Alternate Encoding

References

[REF-172] Chris Wysopal. "Mobile App Top 10 List". 2010-12-13. <http://www.veracode.com/blog/2010/12/mobile-app-top-10-list/>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	PLOVER
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 Likelihood_of_Exploit, Relationships, Taxonomy_Mappings, Weakness_Ordinalities
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Description
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Alternate_Terms, Description, Name
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Taxonomy_Mappings
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Related_Attack_Patterns
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
2012-05-11	CWE Content Team	MITRE
2012-05-11	updated Related_Attack_Patterns, 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 Alternate_Terms, Applicable_Platforms, References
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Related_Attack_Patterns
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
2017-05-03	CWE Content Team	MITRE
2017-05-03	updated Related_Attack_Patterns
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated References
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Related_Attack_Patterns
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Related_Attack_Patterns, Relationships
2019-09-19	CWE Content Team	MITRE
2019-09-19	updated Demonstrative_Examples, Observed_Examples, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Applicable_Platforms, Demonstrative_Examples, Description, Name, Observed_Examples, Related_Attack_Patterns, Relationships, Weakness_Ordinalities
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Relationships
2020-08-20	CWE Content Team	MITRE
2020-08-20	updated Alternate_Terms, Description, Maintenance_Notes, Related_Attack_Patterns, Relationships
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Potential_Mitigations
Previous Entry Names
Change Date	Previous Entry Name
2009-12-28	Information Leak (Information Disclosure)

2020-02-24	Information Exposure

Weakness ID: 73

Abstraction: Base
Structure: Simple

Status: Draft

Presentation Filter:

Description

The software allows user input to control or influence paths or file names that are used in filesystem operations.

Extended Description

This could allow an attacker to access or modify system files or other files that are critical to the application.

Path manipulation errors occur when the following two conditions are met:

1. An attacker can specify a path used in an operation on the filesystem.

2. By specifying the resource, the attacker gains a capability that would not otherwise be permitted.

For example, the program may give the attacker the ability to overwrite the specified file or run with a configuration controlled by the attacker.

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.	642	External Control of Critical State Data
ParentOf	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.	114	Process Control
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.	22	Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
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.	41	Improper Resolution of Path Equivalence
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.	59	Improper Link Resolution Before File Access ('Link Following')
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.	98	Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')
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.	434	Unrestricted Upload of File with Dangerous Type

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 "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

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

Applicable Platforms

Languages

Class: Language-Independent (Undetermined Prevalence)

Operating Systems

Class: Unix (Often Prevalent)

Class: Windows (Often Prevalent)

Class: macOS (Often Prevalent)

Common Consequences

Scope	Impact	Likelihood
Integrity Confidentiality	Technical Impact: Read Files or Directories; Modify Files or Directories The application can operate on unexpected files. Confidentiality is violated when the targeted filename is not directly readable by the attacker.
Integrity Confidentiality Availability	Technical Impact: Modify Files or Directories; Execute Unauthorized Code or Commands The application can operate on unexpected files. This may violate integrity if the filename is written to, or if the filename is for a program or other form of executable code.
Availability	Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (Other) The application can operate on unexpected files. Availability can be violated if the attacker specifies an unexpected file that the application modifies. Availability can also be affected if the attacker specifies a filename for a large file, or points to a special device or a file that does not have the format that the application expects.

Likelihood Of Exploit

High

Demonstrative Examples

Example 1

The following code uses input from an HTTP request to create a file name. The programmer has not considered the possibility that an attacker could provide a file name such as "../../tomcat/conf/server.xml", which causes the application to delete one of its own configuration files (CWE-22).

(bad code)

Example Language: Java

String rName = request.getParameter("reportName");
File rFile = new File("/usr/local/apfr/reports/" + rName);
...
rFile.delete();

Example 2

The following code uses input from a configuration file to determine which file to open and echo back to the user. If the program runs with privileges and malicious users can change the configuration file, they can use the program to read any file on the system that ends with the extension .txt.

(bad code)

Example Language: Java

fis = new FileInputStream(cfg.getProperty("sub")+".txt");
amt = fis.read(arr);
out.println(arr);

Observed Examples

Reference	Description
CVE-2008-5748	Chain: external control of values for user's desired language and theme enables path traversal.
CVE-2008-5764	Chain: external control of user's target language enables remote file inclusion.

Potential Mitigations

Phase: Architecture and Design

When the set of filenames is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames, and reject all other inputs. For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt". Features such as the ESAPI AccessReferenceMap provide this capability.

Phases: Architecture and Design; Operation

Run your code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict all access to files within a particular directory.

Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection.

This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise.

Be careful to avoid CWE-243 and other weaknesses related to jails.

Phase: Architecture and Design

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Phase: Implementation

Strategy: Input Validation

When validating filenames, use stringent allowlists that limit the character set to be used. If feasible, only allow a single "." character in the filename to avoid weaknesses such as CWE-23, and exclude directory separators such as "/" to avoid CWE-36. Use a list of allowable file extensions, which will help to avoid CWE-434.

Do not rely exclusively on a filtering mechanism that removes potentially dangerous characters. This is equivalent to a denylist, which may be incomplete (CWE-184). For example, filtering "/" is insufficient protection if the filesystem also supports the use of "\" as a directory separator. Another possible error could occur when the filtering is applied in a way that still produces dangerous data (CWE-182). For example, if "../" sequences are removed from the ".../...//" string in a sequential fashion, two instances of "../" would be removed from the original string, but the remaining characters would still form the "../" string.

Effectiveness: High

Phase: Implementation

Use a built-in path canonicalization function (such as realpath() in C) that produces the canonical version of the pathname, which effectively removes ".." sequences and symbolic links (CWE-23, CWE-59).

Phases: Installation; Operation

Use OS-level permissions and run as a low-privileged user to limit the scope of any successful attack.

Phases: Operation; Implementation

If you are using PHP, configure your application so that it does not use register_globals. During implementation, develop your application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.

Phase: Testing

Use automated static analysis tools that target this type of weakness. Many modern techniques use data flow analysis to minimize the number of false positives. This is not a perfect solution, since 100% accuracy and coverage are not feasible.

Phase: Testing

Use 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.

Phase: Testing

Use tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session. These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.

Weakness Ordinalities

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

Detection Methods

Automated Static Analysis

The external control or influence of filenames can often be detected using automated static analysis that models data flow within the software.

Automated static analysis might not be able to recognize when proper input validation is being performed, leading to false positives - i.e., warnings that do not have any security consequences or require any code changes.

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	723	OWASP Top Ten 2004 Category A2 - Broken Access Control
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	752	2009 Top 25 - Risky Resource Management
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.	981	SFP Secondary Cluster: Path Traversal

Notes

Maintenance

CWE-114 is a Class, but it is listed a child of CWE-73 in view 1000. This suggests some abstraction problems that should be resolved in future versions.

Relationship

The external control of filenames can be the primary link in chains with other file-related weaknesses, as seen in the CanPrecede relationships. This is because software systems use files for many different purposes: to execute programs, load code libraries, to store application data, to store configuration settings, record temporary data, act as signals or semaphores to other processes, etc.

However, those weaknesses do not always require external control. For example, link-following weaknesses (CWE-59) often involve pathnames that are not controllable by the attacker at all.

The external control can be resultant from other issues. For example, in PHP applications, the register_globals setting can allow an attacker to modify variables that the programmer thought were immutable, enabling file inclusion (CWE-98) and path traversal (CWE-22). Operating with excessive privileges (CWE-250) might allow an attacker to specify an input filename that is not directly readable by the attacker, but is accessible to the privileged program. A buffer overflow (CWE-119) might give an attacker control over nearby memory locations that are related to pathnames, but were not directly modifiable by the attacker.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
7 Pernicious Kingdoms			Path Manipulation
Software Fault Patterns	SFP16		Path Traversal

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-13	Subverting Environment Variable Values
CAPEC-267	Leverage Alternate Encoding
CAPEC-64	Using Slashes and URL Encoding Combined to Bypass Validation Logic
CAPEC-72	URL Encoding
CAPEC-76	Manipulating Web Input to File System Calls
CAPEC-78	Using Escaped Slashes in Alternate Encoding
CAPEC-79	Using Slashes in Alternate Encoding
CAPEC-80	Using UTF-8 Encoding to Bypass Validation Logic

References

[REF-45] OWASP. "OWASP Enterprise Security API (ESAPI) Project". <http://www.owasp.org/index.php/ESAPI>.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	7 Pernicious Kingdoms
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
2009-01-12	CWE Content Team	MITRE
2009-01-12	updated Applicable_Platforms, Causal_Nature, Common_Consequences, Demonstrative_Examples, Description, Observed_Examples, Other_Notes, Potential_Mitigations, References, Relationship_Notes, Relationships, Weakness_Ordinalities
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Potential_Mitigations, Relationships
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Demonstrative_Examples
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Common_Consequences, Description
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Detection_Factors
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated Potential_Mitigations
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 Demonstrative_Examples, References, Related_Attack_Patterns, 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 Applicable_Platforms, Likelihood_of_Exploit, Modes_of_Introduction, Relationships, Taxonomy_Mappings
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Potential_Mitigations, References, Relationships, Time_of_Introduction, Type
2020-06-25	CWE Content Team	MITRE
2020-06-25	updated Potential_Mitigations, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Maintenance_Notes, Potential_Mitigations
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Path Manipulation

Weakness ID: 610

Abstraction: Class
Structure: Simple

Status: Draft

Presentation Filter:

Description

The product uses an externally controlled name or reference that resolves to a resource that is outside of the intended control sphere.

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
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.	15	External Control of System or Configuration Setting
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.	73	External Control of File Name or Path
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.	384	Session Fixation
ParentOf	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.	441	Unintended Proxy or Intermediary ('Confused Deputy')
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.	470	Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
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.	601	URL Redirection to Untrusted Site ('Open Redirect')
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.	611	Improper Restriction of XML External Entity Reference
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

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

Nature	Type	ID	Name
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.	384	Session Fixation
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.	601	URL Redirection to Untrusted Site ('Open Redirect')
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.	611	Improper Restriction of XML External Entity Reference
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.	918	Server-Side Request Forgery (SSRF)
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.	1021	Improper Restriction of Rendered UI Layers or Frames

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	COMMISSION: This weakness refers to an incorrect design related to an architectural security tactic.

Common Consequences

Scope	Impact	Likelihood
Confidentiality Integrity	Technical Impact: Read Application Data; Modify Application Data

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	980	SFP Secondary Cluster: Link in Resource Name Resolution
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

Notes

Maintenance

The relationship between CWE-99 and CWE-610 needs further investigation and clarification. They might be duplicates. CWE-99 "Resource Injection," as originally defined in Seven Pernicious Kingdoms taxonomy, emphasizes the "identifier used to access a system resource" such as a file name or port number, yet it explicitly states that the "resource injection" term does not apply to "path manipulation," which effectively identifies the path at which a resource can be found and could be considered to be one aspect of a resource identifier. Also, CWE-610 effectively covers any type of resource, whether that resource is at the system layer, the application layer, or the code layer.

Relationship

This is a general class of weakness, but most research is focused on more specialized cases, such as path traversal (CWE-22) and symlink following (CWE-61). A symbolic link has a name; in general, it appears like any other file in the file system. However, the link includes a reference to another file, often in another directory - perhaps in another sphere of control. Many common library functions that accept filenames will "follow" a symbolic link and use the link's target instead.

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-219	XML Routing Detour Attacks

Content History

Submissions
Submission Date	Submitter	Organization
2007-05-07	Anonymous Tool Vendor (under NDA)
2007-05-07
Modifications
Modification Date	Modifier	Organization
2008-09-08	CWE Content Team	MITRE
2008-09-08	updated Relationships, Other_Notes, Taxonomy_Mappings
2009-10-29	CWE Content Team	MITRE
2009-10-29	updated Other_Notes, Relationship_Notes
2010-04-05	CWE Content Team	MITRE
2010-04-05	updated Related_Attack_Patterns
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 Maintenance_Notes
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
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 Modes_of_Introduction, 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 Relationships
Previous Entry Names
Change Date	Previous Entry Name
2008-04-11	Externally Controlled Reference to an Internal Resource

Weakness ID: 761

Abstraction: Variant
Structure: Simple

Status: Incomplete

Presentation Filter:

Description

The application calls free() on a pointer to a memory resource that was allocated on the heap, but the pointer is not at the start of the buffer.

Extended Description

This can cause the application to crash, or in some cases, modify critical program variables or execute code.

This weakness often occurs when the memory is allocated explicitly on the heap with one of the malloc() family functions and free() is called, but pointer arithmetic has caused the pointer to be in the interior or end of the buffer.

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.	763	Release of Invalid Pointer or Reference

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.	404	Improper Resource Shutdown or Release

Modes Of Introduction

Phase	Note
Implementation

Common Consequences

Scope	Impact	Likelihood
Integrity Availability Confidentiality	Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands

Demonstrative Examples

Example 1

In this example, the programmer dynamically allocates a buffer to hold a string and then searches for a specific character. After completing the search, the programmer attempts to release the allocated memory and return SUCCESS or FAILURE to the caller. Note: for simplification, this example uses a hard-coded "Search Me!" string and a constant string length of 20.

(bad code)

Example Language: C

#define SUCCESS (1)
#define FAILURE (0)

int contains_char(char c){

char *str;
str = (char*)malloc(20*sizeof(char));
strcpy(str, "Search Me!");
while( *str != NULL){

if( *str == c ){

/* matched char, free string and return success */
free(str);
return SUCCESS;

}
/* didn't match yet, increment pointer and try next char */

str = str + 1;

}
/* we did not match the char in the string, free mem and return failure */

free(str);
return FAILURE;

}

However, if the character is not at the beginning of the string, or if it is not in the string at all, then the pointer will not be at the start of the buffer when the programmer frees it.

Instead of freeing the pointer in the middle of the buffer, the programmer can use an indexing pointer to step through the memory or abstract the memory calculations by using array indexing.

(good code)

Example Language: C

#define SUCCESS (1)
#define FAILURE (0)

int cointains_char(char c){

char *str;
int i = 0;
str = (char*)malloc(20*sizeof(char));
strcpy(str, "Search Me!");
while( i < strlen(str) ){

if( str[i] == c ){

/* matched char, free string and return success */
free(str);
return SUCCESS;

}
/* didn't match yet, increment pointer and try next char */

i = i + 1;

}
/* we did not match the char in the string, free mem and return failure */

free(str);
return FAILURE;

}

Example 2

This code attempts to tokenize a string and place it into an array using the strsep function, which inserts a \0 byte in place of whitespace or a tab character. After finishing the loop, each string in the AP array points to a location within the input string.

(bad code)

Example Language: C

char **ap, *argv[10], *inputstring;
for (ap = argv; (*ap = strsep(&inputstring, " \t")) != NULL;)

if (**ap != '\0')

if (++ap >= &argv[10])

break;

/.../
free(ap[4]);

Since strsep is not allocating any new memory, freeing an element in the middle of the array is equivalent to free a pointer in the middle of inputstring.

Example 3

Consider the following code in the context of a parsing application to extract commands out of user data. The intent is to parse each command and add it to a queue of commands to be executed, discarding each malformed entry.

(bad code)

Example Language: C

//hardcode input length for simplicity
char* input = (char*) malloc(40*sizeof(char));
char *tok;
char* sep = " \t";

get_user_input( input );

/* The following loop will parse and process each token in the input string */

tok = strtok( input, sep);
while( NULL != tok ){

if( isMalformed( tok ) ){

/* ignore and discard bad data */
free( tok );

}
else{

add_to_command_queue( tok );

}
tok = strtok( NULL, sep));

}

While the above code attempts to free memory associated with bad commands, since the memory was all allocated in one chunk, it must all be freed together.

One way to fix this problem would be to copy the commands into a new memory location before placing them in the queue. Then, after all commands have been processed, the memory can safely be freed.

(good code)

Example Language: C

//hardcode input length for simplicity
char* input = (char*) malloc(40*sizeof(char));
char *tok, *command;
char* sep = " \t";

get_user_input( input );

/* The following loop will parse and process each token in the input string */

tok = strtok( input, sep);
while( NULL != tok ){

if( !isMalformed( command ) ){

/* copy and enqueue good data */
command = (char*) malloc( (strlen(tok) + 1) * sizeof(char) );
strcpy( command, tok );
add_to_command_queue( command );

}
tok = strtok( NULL, sep));

}

free( input )

Observed Examples

Reference	Description
CVE-2019-11930	function "internally calls 'calloc' and returns a pointer at an index... inside the allocated buffer. This led to freeing invalid memory."

Potential Mitigations

Phase: Implementation

When utilizing pointer arithmetic to traverse a buffer, use a separate variable to track progress through memory and preserve the originally allocated address for later freeing.

Phase: Implementation

When programming in C++, consider using smart pointers provided by the boost library to help correctly and consistently manage memory.

Phase: Architecture and Design

Strategy: Libraries or Frameworks

Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

For example, glibc in Linux provides protection against free of invalid pointers.

Phase: Architecture and Design

Use a language that provides abstractions for memory allocation and deallocation.

Phase: Testing

Use a tool that dynamically detects memory management problems, such as valgrind.

Affected Resources

Memory

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	969	SFP Secondary Cluster: Faulty Memory Release

Notes

Maintenance

Currently, CWE-763 is the parent, however it may be desirable to have an intermediate parent which is not function-specific, similar to how CWE-762 is an intermediate parent between CWE-763 and CWE-590.

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Fit	Mapped Node Name
Software Fault Patterns	SFP12		Faulty Memory Release

References

[REF-657] "boost C++ Library Smart Pointers". <http://www.boost.org/doc/libs/1_38_0/libs/smart_ptr/smart_ptr.htm>.

[REF-480] "Valgrind". <http://valgrind.org/>.

Content History

Submissions
Submission Date	Submitter	Organization
2009-05-08	CWE Content Team	MITRE
2009-05-08
Modifications
Modification Date	Modifier	Organization
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
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
2014-02-18	CWE Content Team	MITRE
2014-02-18	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
2020-12-10	CWE Content Team	MITRE
2020-12-10	updated Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Observed_Examples

Weakness ID: 284

Abstraction: Pillar
Structure: Simple

Status: Incomplete

Presentation Filter:

Description

The software does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Extended Description

Access control involves the use of several protection mechanisms such as:

Authentication (proving the identity of an actor)
Authorization (ensuring that a given actor can access a resource), and
Accountability (tracking of activities that were performed)

When any mechanism is not applied or otherwise fails, attackers can compromise the security of the software by gaining privileges, reading sensitive information, executing commands, evading detection, etc.

There are two distinct behaviors that can introduce access control weaknesses:

Specification: incorrect privileges, permissions, ownership, etc. are explicitly specified for either the user or the resource (for example, setting a password file to be world-writable, or giving administrator capabilities to a guest user). This action could be performed by the program or the administrator.
Enforcement: the mechanism contains errors that prevent it from properly enforcing the specified access control requirements (e.g., allowing the user to specify their own privileges, or allowing a syntactically-incorrect ACL to produce insecure settings). This problem occurs within the program itself, in that it does not actually enforce the intended security policy that the administrator specifies.

Alternate Terms

Authorization:	The terms "access control" and "authorization" are often used interchangeably, although many people have distinct definitions. The CWE usage of "access control" is intended as a general term for the various mechanisms that restrict which users can access which resources, and "authorization" is more narrowly defined. It is unlikely that there will be community consensus on the use of these terms.

Relationships

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

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).	1000	Research Concepts
ParentOf	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.	269	Improper Privilege Management
ParentOf	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.	282	Improper Ownership Management
ParentOf	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.	285	Improper Authorization
ParentOf	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.	286	Incorrect User Management
ParentOf	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.	287	Improper Authentication
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.	346	Origin Validation Error
ParentOf	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.	923	Improper Restriction of Communication Channel to Intended Endpoints
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.	942	Permissive Cross-domain Policy with Untrusted Domains
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.	1220	Insufficient Granularity of Access Control
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.	1224	Improper Restriction of Write-Once Bit Fields
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.	1231	Improper Implementation of Lock Protection Registers
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.	1242	Inclusion of Undocumented Features or Chicken Bits
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.	1252	CPU Hardware Not Configured to Support Exclusivity of Write and Execute Operations
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.	1256	Hardware Features Enable Physical Attacks from Software
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.	1257	Improper Access Control Applied to Mirrored or Aliased Memory Regions
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.	1259	Improper Restriction of Security Token Assignment
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.	1260	Improper Handling of Overlap Between Protected Memory Ranges
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.	1262	Register Interface Allows Software Access to Sensitive Data or Security Settings
ParentOf	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.	1263	Improper Physical Access Control
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.	1267	Policy Uses Obsolete Encoding
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.	1268	Policy Privileges are not Assigned Consistently Between Control and Data Agents
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.	1270	Generation of Incorrect Security Tokens
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.	1274	Insufficient Protections on the Volatile Memory Containing Boot Code
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.	1275	Sensitive Cookie with Improper SameSite Attribute
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.	1276	Hardware Child Block Incorrectly Connected to Parent System
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.	1280	Access Control Check Implemented After Asset is Accessed
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.	1283	Mutable Attestation or Measurement Reporting Data
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.	1290	Incorrect Decoding of Security Identifiers
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.	1292	Incorrect Conversion of Security Identifiers
ParentOf	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.	1294	Insecure Security Identifier Mechanism
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.	1296	Incorrect Chaining or Granularity of Debug Components
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.	1304	Improperly Preserved Integrity of Hardware Configuration State During a Power Save/Restore Operation
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.	1311	Improper Translation of Security Attributes by Fabric Bridge
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.	1312	Missing Protection for Mirrored Regions in On-Chip Fabric Firewall
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.	1313	Hardware Allows Activation of Test or Debug Logic at Runtime
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.	1315	Improper Setting of Bus Controlling Capability in Fabric End-point
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.	1316	Fabric-Address Map Allows Programming of Unwarranted Overlaps of Protected and Unprotected Ranges
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.	1317	Missing Security Checks in Fabric Bridge
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.	1320	Improper Protection for Out of Bounds Signal Level Alerts
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.	1323	Improper Management of Sensitive Trace Data
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.	1334	Unauthorized Error Injection Can Degrade Hardware Redundancy

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.	1011	Authorize Actors

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

Nature	Type	ID	Name
ParentOf	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.	285	Improper Authorization
ParentOf	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.	287	Improper Authentication
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.	288	Authentication Bypass Using an Alternate Path or Channel
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.	639	Authorization Bypass Through User-Controlled Key
ParentOf	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.	862	Missing Authorization
ParentOf	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.	863	Incorrect Authorization

Modes Of Introduction

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

Common Consequences

Scope	Impact	Likelihood
Other	Technical Impact: Varies by Context

Observed Examples

Reference	Description
CVE-2010-4624	Bulletin board applies restrictions on number of images during post creation, but does not enforce this on editing.

Potential Mitigations

Phases: Architecture and Design; Operation

Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.

Phase: Architecture and Design

Strategy: Separation of Privilege

Affected Resources

File or Directory

Memberships

Nature	Type	ID	Name
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	254	7PK - Security Features
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	723	OWASP Top Ten 2004 Category A2 - Broken Access Control
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	944	SFP Secondary Cluster: Access Management
MemberOf	Category - a CWE entry that contains a set of other entries that share a common characteristic.	1031	OWASP Top Ten 2017 Category A5 - Broken Access 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).	1340	CISQ Data Protection Measures

Notes

Maintenance

This entry needs more work. Possible sub-categories include:

Trusted group includes undesired entities (partially covered by CWE-286)
Group can perform undesired actions
ACL parse error does not fail closed

Taxonomy Mappings

Mapped Taxonomy Name	Node ID	Mapped Node Name
PLOVER		Access Control List (ACL) errors
WASC	2	Insufficient Authorization
7 Pernicious Kingdoms		Missing Access Control

Related Attack Patterns

CAPEC-ID	Attack Pattern Name
CAPEC-19	Embedding Scripts within Scripts
CAPEC-441	Malicious Logic Insertion
CAPEC-478	Modification of Windows Service Configuration
CAPEC-479	Malicious Root Certificate
CAPEC-502	Intent Spoof
CAPEC-503	WebView Exposure
CAPEC-536	Data Injected During Configuration
CAPEC-546	Probe Application Memory
CAPEC-550	Install New Service
CAPEC-551	Modify Existing Service
CAPEC-552	Install Rootkit
CAPEC-556	Replace File Extension Handlers
CAPEC-558	Replace Trusted Executable
CAPEC-562	Modify Shared File
CAPEC-563	Add Malicious File to Shared Webroot
CAPEC-564	Run Software at Logon
CAPEC-578	Disable Security Software

References

[REF-7] Michael Howard and David LeBlanc. "Writing Secure Code". Chapter 6, "Determining Appropriate Access Control" Page 171. 2nd Edition. Microsoft Press. 2002-12-04. <https://www.microsoftpressstore.com/store/writing-secure-code-9780735617223>.

[REF-44] Michael Howard, David LeBlanc and John Viega. "24 Deadly Sins of Software Security". "Sin 17: Failure to Protect Stored Data." Page 253. McGraw-Hill. 2010.

Content History

Submissions
Submission Date	Submitter	Organization
2006-07-19	PLOVER
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 Alternate_Terms, Background_Details, Description, Maintenance_Notes, Name, Relationships, Taxonomy_Mappings
2008-10-14	CWE Content Team	MITRE
2008-10-14	updated Relationships
2009-03-10	CWE Content Team	MITRE
2009-03-10	updated Relationships
2009-07-27	CWE Content Team	MITRE
2009-07-27	updated Alternate_Terms, Relationships
2009-12-28	CWE Content Team	MITRE
2009-12-28	updated Potential_Mitigations
2010-02-16	CWE Content Team	MITRE
2010-02-16	updated References, Taxonomy_Mappings
2010-06-21	CWE Content Team	MITRE
2010-06-21	updated Potential_Mitigations
2011-03-24	CWE Content Team	MITRE
2011-03-24	Changed name and description; clarified difference between "access control" and "authorization."
2011-03-29	CWE Content Team	MITRE
2011-03-29	updated Alternate_Terms, Background_Details, Description, Maintenance_Notes, Name, 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 References, Relationships
2012-10-30	CWE Content Team	MITRE
2012-10-30	updated Potential_Mitigations
2014-02-18	CWE Content Team	MITRE
2014-02-18	updated Related_Attack_Patterns, Relationships
2014-06-23	CWE Content Team	MITRE
2014-06-23	updated Relationships
2014-07-30	CWE Content Team	MITRE
2014-07-30	updated Relationships
2015-12-07	CWE Content Team	MITRE
2015-12-07	updated Relationships
2017-11-08	CWE Content Team	MITRE
2017-11-08	updated Affected_Resources, Modes_of_Introduction, Observed_Examples, References, Relationships
2018-03-27	CWE Content Team	MITRE
2018-03-27	updated References, Relationships
2019-01-03	CWE Content Team	MITRE
2019-01-03	updated Related_Attack_Patterns
2019-06-20	CWE Content Team	MITRE
2019-06-20	updated Related_Attack_Patterns, Relationships
2020-02-24	CWE Content Team	MITRE
2020-02-24	updated Relationships, Taxonomy_Mappings, Type
2020-06-25	CWE Content Team	MITRE
2020-06-25	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 Potential_Mitigations, Relationships
2021-03-15	CWE Content Team	MITRE
2021-03-15	updated Maintenance_Notes, Relationships
Previous Entry Names
Change Date	Previous Entry Name
2008-09-09	Access Control Issues

2011-03-29	Access Control (Authorization) Issues

Common Weakness Enumeration

CWE VIEW: Entries with Maintenance Notes

View Components

CWE-824: Access of Uninitialized Pointer

CWE-767: Access to Critical Private Variable via Public Method

CWE-670: Always-Incorrect Control Flow Implementation

CWE-1282: Assumed-Immutable Data is Stored in Writable Memory

CWE-300: Channel Accessible by Non-Endpoint

CWE-1255: Comparison Logic is Vulnerable to Power Side-Channel Attacks

CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CWE CATEGORY: Configuration

CWE CATEGORY: Cryptographic Issues

CWE-502: Deserialization of Untrusted Data

CWE-1273: Device Unlock Credential Sharing

CWE-172: Encoding Error

CWE-250: Execution with Unnecessary Privileges

CWE-825: Expired Pointer Dereference

CWE-1191: Exposed Chip Debug and Test Interface With Insufficient or Missing Authorization

CWE-359: Exposure of Private Personal Information to an Unauthorized Actor

CWE-213: Exposure of Sensitive Information Due to Incompatible Policies

CWE-202: Exposure of Sensitive Information Through Data Queries

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

CWE-73: External Control of File Name or Path

CWE-610: Externally Controlled Reference to a Resource in Another Sphere

CWE-234: Failure to Handle Missing Parameter

CWE-1277: Firmware Not Updateable

CWE-761: Free of Pointer not at Start of Buffer

CWE-1256: Hardware Features Enable Physical Attacks from Software

CWE-284: Improper Access Control

CWE-1244: Improper Access to Sensitive Information Using Debug and Test Interfaces

CWE-664: Improper Control of a Resource Through its Lifetime