CWE-206 Detail

CWE-206

Observable Internal Behavioral Discrepancy
Incomplete
2006-07-19
00h00 +00:00
2023-06-29
00h00 +00:00
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Name: Observable Internal Behavioral Discrepancy

The product performs multiple behaviors that are combined to produce a single result, but the individual behaviors are observable separately in a way that allows attackers to reveal internal state or internal decision points.

CWE Description

Ideally, a product should provide as little information as possible to an attacker. Any hints that the attacker may be making progress can then be used to simplify or optimize the attack. For example, in a login procedure that requires a username and password, ultimately there is only one decision: success or failure. However, internally, two separate actions are performed: determining if the username exists, and checking if the password is correct. If the product behaves differently based on whether the username exists or not, then the attacker only needs to concentrate on the password.

General Informations

Modes Of Introduction

Architecture and Design
Implementation

Applicable Platforms

Language

Class: Not Language-Specific (Undetermined)

Common Consequences

Scope Impact Likelihood
Confidentiality
Access Control
Read Application Data, Bypass Protection Mechanism

Observed Examples

References Description

CVE-2002-2031

File existence via infoleak monitoring whether "onerror" handler fires or not.

CVE-2005-2025

Valid groupname enumeration via behavioral infoleak (sends response if valid, doesn't respond if not).

CVE-2001-1497

Behavioral infoleak in GUI allows attackers to distinguish between alphanumeric and non-alphanumeric characters in a password, thus reducing the search space.

CVE-2003-0190

Product immediately sends an error message when user does not exist instead of waiting until the password is provided, allowing username enumeration.

Potential Mitigations

Setup generic response pages for error conditions. 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.

Vulnerability Mapping Notes

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

Submission

Name Organization Date Date release Version
PLOVER 2006-07-19 +00:00 2006-07-19 +00:00 Draft 3

Modifications

Name Organization Date Comment
Eric Dalci Cigital 2008-07-01 +00:00 updated Potential_Mitigations, Time_of_Introduction
CWE Content Team MITRE 2008-09-08 +00:00 updated Relationships, Taxonomy_Mappings
CWE Content Team MITRE 2011-03-29 +00:00 updated Name
CWE Content Team MITRE 2011-06-01 +00:00 updated Common_Consequences
CWE Content Team MITRE 2012-05-11 +00:00 updated Relationships
CWE Content Team MITRE 2012-10-30 +00:00 updated Potential_Mitigations
CWE Content Team MITRE 2014-07-30 +00:00 updated Relationships
CWE Content Team MITRE 2017-11-08 +00:00 updated Applicable_Platforms
CWE Content Team MITRE 2020-02-24 +00:00 updated Description, Name, Potential_Mitigations, Relationships
CWE Content Team MITRE 2023-04-27 +00:00 updated Relationships
CWE Content Team MITRE 2023-06-29 +00:00 updated Mapping_Notes