Internal Behavioral Inconsistency Information Leak
Weakness ID: 206 (Weakness Variant)Status: Incomplete
+ Description

Description Summary

Two separate operations in a product cause the product to behave differently in a way that is observable to an attacker and reveals security-relevant information about the internal state of the product, such as whether a particular operation was successful or not.
+ Time of Introduction
  • Architecture and Design
  • Implementation
+ Applicable Platforms



+ Observed Examples
CVE-2002-2031File existence via infoleak monitoring whether "onerror" handler fires or not.
CVE-2005-2025Valid groupname enumeration via behavioral infoleak (sends response if valid, doesn't respond if not).
CVE-2001-1497Behavioral infoleak in GUI allows attackers to distinguish between alphanumeric and non-alphanumeric characters in a password, thus reducing the search space.
CVE-2003-0190Product immediately sends an error message when user does not exist instead of waiting until the password is provided, allowing username enumeration.
+ Potential Mitigations

Compartmentalize your 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.

Setup generic response pages for error condition. The error page should not disclose information about the success or failure of a sensitive operation. For instance, the login page should not confirm that the login is correct and the password incorrect. The attacker who tries random account name may be able to guess some of them. Confirming that the account exists would make the login page more susceptible to brute force attack.

+ Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness BaseWeakness Base205Information Exposure Through Behavioral Discrepancy
Development Concepts (primary)699
Research Concepts (primary)1000
+ Taxonomy Mappings
Mapped Taxonomy NameNode IDFitMapped Node Name
PLOVERInternal behavioral inconsistency infoleak
+ Content History
Submission DateSubmitterOrganizationSource
PLOVERExternally Mined
Modification DateModifierOrganizationSource
2008-07-01Eric DalciCigitalExternal
updated Potential Mitigations, Time of Introduction
2008-09-08CWE Content TeamMITREInternal
updated Relationships, Taxonomy Mappings