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Common Weakness Enumeration

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CWE-76: Improper Neutralization of Equivalent Special Elements

 
Improper Neutralization of Equivalent Special Elements
Weakness ID: 76 (Weakness Base)Status: Draft
+ Description

Description Summary

The software properly neutralizes certain special elements, but it improperly neutralizes equivalent special elements.

Extended Description

The software may have a fixed list of special characters it believes is complete. However, there may be alternate encodings, or representations that also have the same meaning. For example, the software may filter out a leading slash (/) to prevent absolute path names, but does not account for a tilde (~) followed by a user name, which on some *nix systems could be expanded to an absolute pathname. Alternately, the software might filter a dangerous "-e" command-line switch when calling an external program, but it might not account for "--exec" or other switches that have the same semantics.

+ Time of Introduction
  • Architecture and Design
  • Implementation
+ Applicable Platforms

Languages

All

+ Common Consequences
ScopeEffect
Other

Technical Impact: Other

+ Likelihood of Exploit

High to Very High

+ Potential Mitigations

Phase: Requirements

Programming languages and supporting technologies might be chosen which are not subject to these issues.

Phase: Implementation

Utilize an appropriate mix of white-list and black-list parsing to filter equivalent special element syntax from all input.

+ Weakness Ordinalities
OrdinalityDescription
Primary
(where the weakness exists independent of other weaknesses)
+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness ClassWeakness Class75Failure to Sanitize Special Elements into a Different Plane (Special Element Injection)
Development Concepts (primary)699
Research Concepts (primary)1000
ChildOfCategoryCategory896SFP Cluster: Tainted Input
Software Fault Pattern (SFP) Clusters (primary)888
+ Causal Nature

Explicit

+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
PLOVEREquivalent Special Element Injection
+ Content History
Submissions
Submission DateSubmitterOrganizationSource
PLOVERExternally Mined
Modifications
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Time_of_Introduction
2008-09-08CWE Content TeamMITREInternal
updated Relationships, Other_Notes, Taxonomy_Mappings, Weakness_Ordinalities
2009-10-29CWE Content TeamMITREInternal
updated Description, Other_Notes
2010-06-21CWE Content TeamMITREInternal
updated Description, Name
2010-12-13CWE Content TeamMITREInternal
updated Description
2011-06-01CWE Content TeamMITREInternal
updated Common_Consequences
2012-05-11CWE Content TeamMITREInternal
updated Relationships
2012-10-30CWE Content TeamMITREInternal
updated Potential_Mitigations
Previous Entry Names
Change DatePrevious Entry Name
2008-04-11Equivalent Special Element Injection
2010-06-21Failure to Resolve Equivalent Special Elements into a Different Plane
Page Last Updated: February 18, 2014