Permissive Whitelist
Weakness ID: 183 (Weakness Base)Status: Draft
+ Description

Description Summary

An application uses a "whitelist" of acceptable values, but the whitelist includes at least one unsafe value, leading to resultant weaknesses.
+ Time of Introduction
  • Implementation
+ Applicable Platforms

Languages

All

+ Potential Mitigations

Define rigid requirements specifications for input and strictly accept input based on those specifications. Determine if any of the valid data include special characters that are associated with security exploits (use this taxonomy and the Common Vulnerabilities and Exposures as a start to determine what characters are potentially malicious). If permitted, then follow the potential mitigations associated with the weaknesses in this taxonomy. Always handle these data carefully and anticipate attempts to exploit your system.

Phase: Architecture and Design

Assume all input is malicious. Use a standard input validation mechanism to validate all input for length, type, syntax, and business rules before accepting the data to be displayed or stored. Use an "accept known good" validation strategy.

+ Weakness Ordinalities
OrdinalityDescription
Primary
(where the weakness exists independent of other weaknesses)
+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfCategoryCategory171Cleansing, Canonicalization, and Comparison Errors
Development Concepts (primary)699
ChildOfWeakness ClassWeakness Class693Protection Mechanism Failure
Research Concepts (primary)1000
ChildOfWeakness ClassWeakness Class697Insufficient Comparison
Research Concepts1000
ChildOfCategoryCategory722OWASP Top Ten 2004 Category A1 - Unvalidated Input
Weaknesses in OWASP Top Ten (2004) (primary)711
CanPrecedeWeakness BaseWeakness Base434Unrestricted Upload of File with Dangerous Type
Research Concepts1000
PeerOfWeakness BaseWeakness Base625Permissive Regular Expression
Research Concepts1000
PeerOfWeakness BaseWeakness Base627Dynamic Variable Evaluation
Research Concepts1000
CanAlsoBeWeakness BaseWeakness Base186Overly Restrictive Regular Expression
Research Concepts1000
+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
PLOVERPermissive Whitelist
+ Related Attack Patterns
CAPEC-IDAttack Pattern Name
(CAPEC Version: 1.4)
3Using Leading 'Ghost' Character Sequences to Bypass Input Filters
43Exploiting Multiple Input Interpretation Layers
71Using Unicode Encoding to Bypass Validation Logic
+ Content History
Submissions
Submission DateSubmitterOrganizationSource
PLOVERExternally Mined
Modifications
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Potential Mitigations, Time of Introduction
2008-09-08CWE Content TeamMITREInternal
updated Description, Relationships, Taxonomy Mappings, Weakness Ordinalities
2009-03-10CWE Content TeamMITREInternal
updated Relationships
2009-07-27CWE Content TeamMITREInternal
updated Potential Mitigations