CWE

Common Weakness Enumeration

A community-developed list of SW & HW weaknesses that can become vulnerabilities

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ID

CWE-394: Unexpected Status Code or Return Value

Weakness ID: 394
Vulnerability Mapping: ALLOWEDThis CWE ID may be used to map to real-world vulnerabilities
Abstraction: BaseBase - a weakness that is still mostly independent of a resource or technology, but with sufficient details to provide specific methods for detection and prevention. Base level weaknesses typically describe issues in terms of 2 or 3 of the following dimensions: behavior, property, technology, language, and resource.
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+ Description
The product does not properly check when a function or operation returns a value that is legitimate for the function, but is not expected by the product.
+ Relationships
Section HelpThis table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.
+ Relevant to the view "Research Concepts" (CWE-1000)
NatureTypeIDName
ChildOfClassClass - 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.754Improper Check for Unusual or Exceptional Conditions
Section HelpThis table shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.
+ Relevant to the view "Software Development" (CWE-699)
NatureTypeIDName
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.389Error Conditions, Return Values, Status Codes
+ Modes Of Introduction
Section HelpThe 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.
PhaseNote
Implementation
+ Applicable Platforms
Section HelpThis listing shows possible areas for which the given weakness could appear. These may be for specific named Languages, Operating Systems, Architectures, Paradigms, Technologies, or a class of such platforms. The platform is listed along with how frequently the given weakness appears for that instance.

Languages

Class: Not Language-Specific (Undetermined Prevalence)

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

Technical Impact: Unexpected State; Alter Execution Logic

+ Observed Examples
ReferenceDescription
Certain packets (zero byte and other lengths) cause a recvfrom call to produce an unexpected return code that causes a server's listening loop to exit.
Unchecked return code from recv() leads to infinite loop.
Kernel function does not properly handle when a null is returned by a function call, causing it to call another function that it shouldn't.
Memory not properly cleared when read() function call returns fewer bytes than expected.
Bypass access restrictions when connecting from IP whose DNS reverse lookup does not return a hostname.
Bypass access restrictions when connecting from IP whose DNS reverse lookup does not return a hostname.
Game server doesn't check return values for functions that handle text strings and associated size values.
Resultant infinite loop when function call returns -1 value.
+ Memberships
Section HelpThis 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.
NatureTypeIDName
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.728OWASP Top Ten 2004 Category A7 - Improper Error Handling
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.962SFP Secondary Cluster: Unchecked Status Condition
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.1181SEI CERT Perl Coding Standard - Guidelines 03. Expressions (EXP)
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.1306CISQ Quality Measures - Reliability
MemberOfCategoryCategory - a CWE entry that contains a set of other entries that share a common characteristic.1405Comprehensive Categorization: Improper Check or Handling of Exceptional Conditions
+ Vulnerability Mapping Notes

Usage: ALLOWED

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

Reason: Acceptable-Use

Rationale:

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

Comments:

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

Relationship

Usually primary, but can be resultant from issues such as behavioral change or API abuse. This can produce resultant vulnerabilities.
+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
PLOVERUnexpected Status Code or Return Value
Software Fault PatternsSFP4Unchecked Status Condition
SEI CERT Perl Coding StandardEXP00-PLImpreciseDo not return undef
+ Content History
+ Submissions
Submission DateSubmitterOrganization
2006-07-19
(CWE Draft 3, 2006-07-19)
PLOVER
+ Modifications
Modification DateModifierOrganization
2008-07-01Eric DalciCigital
updated Time_of_Introduction
2008-09-08CWE Content TeamMITRE
updated Relationships, Other_Notes, Taxonomy_Mappings
2009-03-10CWE Content TeamMITRE
updated Relationships
2009-12-28CWE Content TeamMITRE
updated Other_Notes, Relationship_Notes
2011-06-01CWE Content TeamMITRE
updated Common_Consequences
2011-06-27CWE Content TeamMITRE
updated Common_Consequences
2012-05-11CWE Content TeamMITRE
updated Relationships
2014-07-30CWE Content TeamMITRE
updated Relationships, Taxonomy_Mappings
2017-11-08CWE Content TeamMITRE
updated Applicable_Platforms, Taxonomy_Mappings
2019-01-03CWE Content TeamMITRE
updated Taxonomy_Mappings
2020-08-20CWE Content TeamMITRE
updated Relationships
2021-03-15CWE Content TeamMITRE
updated Relationships
2023-01-31CWE Content TeamMITRE
updated Description
2023-04-27CWE Content TeamMITRE
updated Relationships, Time_of_Introduction
2023-06-29CWE Content TeamMITRE
updated Mapping_Notes
Page Last Updated: February 29, 2024