CWE-412 Detail

CWE-412

Unrestricted Externally Accessible Lock
Incomplete
2006-07-19
00h00 +00:00
2023-06-29
00h00 +00:00
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Name: Unrestricted Externally Accessible Lock

The product properly checks for the existence of a lock, but the lock can be externally controlled or influenced by an actor that is outside of the intended sphere of control.

CWE Description

This prevents the product from acting on associated resources or performing other behaviors that are controlled by the presence of the lock. Relevant locks might include an exclusive lock or mutex, or modifying a shared resource that is treated as a lock. If the lock can be held for an indefinite period of time, then the denial of service could be permanent.

General Informations

Modes Of Introduction

Architecture and Design
Implementation

Applicable Platforms

Language

Class: Not Language-Specific (Undetermined)

Common Consequences

Scope Impact Likelihood
AvailabilityDoS: Resource Consumption (Other)

Note: When an attacker can control a lock, the program may wait indefinitely until the attacker releases the lock, causing a denial of service to other users of the program. This is especially problematic if there is a blocking operation on the lock.

Observed Examples

References Description

CVE-2001-0682

Program can not execute when attacker obtains a mutex.

CVE-2002-1914

Program can not execute when attacker obtains a lock on a critical output file.

CVE-2002-1915

Program can not execute when attacker obtains a lock on a critical output file.

CVE-2002-0051

Critical file can be opened with exclusive read access by user, preventing application of security policy. Possibly related to improper permissions, large-window race condition.

CVE-2000-0338

Chain: predictable file names used for locking, allowing attacker to create the lock beforehand. Resultant from permissions and randomness.

CVE-2000-1198

Chain: Lock files with predictable names. Resultant from randomness.

CVE-2002-1869

Product does not check if it can write to a log file, allowing attackers to avoid logging by accessing the file using an exclusive lock. Overlaps unchecked error condition. This is not quite CWE-412, but close.

Potential Mitigations

Phases : Architecture and Design // Implementation
Use any access control that is offered by the functionality that is offering the lock.
Phases : Architecture and Design // Implementation
Use unpredictable names or identifiers for the locks. This might not always be possible or feasible.
Phases : Architecture and Design
Consider modifying your code to use non-blocking synchronization methods.

Detection Methods

White Box

Automated code analysis techniques might not be able to reliably detect this weakness, since the application's behavior and general security model dictate which resource locks are critical. Interpretation of the weakness might require knowledge of the environment, e.g. if the existence of a file is used as a lock, but the file is created in a world-writable directory.

Vulnerability Mapping Notes

Justification : 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.
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.

Related Attack Patterns

CAPEC-ID Attack Pattern Name
CAPEC-25 Forced Deadlock
The adversary triggers and exploits a deadlock condition in the target software to cause a denial of service. A deadlock can occur when two or more competing actions are waiting for each other to finish, and thus neither ever does. Deadlock conditions can be difficult to detect.

NotesNotes

This overlaps Insufficient Resource Pool when the "pool" is of size 1. It can also be resultant from race conditions, although the timing window could be quite large in some cases.

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
KDM Analytics 2008-08-01 +00:00 added/updated white box definitions
Veracode 2008-08-15 +00:00 Suggested OWASP Top Ten 2004 mapping
CWE Content Team MITRE 2008-09-08 +00:00 updated Common_Consequences, Description, Detection_Factors, Relationships, Observed_Example, Relationship_Notes, Taxonomy_Mappings
CWE Content Team MITRE 2008-10-14 +00:00 updated Description
KDM Analytics 2009-07-17 +00:00 Suggested a better name and the minimal relationship with resources regardless of their criticality.
KDM Analytics 2009-07-17 +00:00 Added a White_Box_Definition and clarified the consequences.
CWE Content Team MITRE 2009-07-27 +00:00 updated Common_Consequences, Description, Name, Potential_Mitigations, White_Box_Definitions
CWE Content Team MITRE 2011-03-29 +00:00 updated Demonstrative_Examples
CWE Content Team MITRE 2011-06-01 +00:00 updated Common_Consequences, Relationships, Taxonomy_Mappings
CWE Content Team MITRE 2012-05-11 +00:00 updated Demonstrative_Examples, Relationships
CWE Content Team MITRE 2014-07-30 +00:00 updated Relationships, Taxonomy_Mappings
CWE Content Team MITRE 2017-11-08 +00:00 updated Applicable_Platforms, Relationships, White_Box_Definitions
CWE Content Team MITRE 2019-01-03 +00:00 updated Relationships, Taxonomy_Mappings
CWE Content Team MITRE 2020-02-24 +00:00 updated Relationships
CWE Content Team MITRE 2023-01-31 +00:00 updated Description
CWE Content Team MITRE 2023-04-27 +00:00 updated Relationships
CWE Content Team MITRE 2023-06-29 +00:00 updated Mapping_Notes