CVE-2021-46149 : Exploit Details and Defense Strategies

An issue in MediaWiki before versions 1.35.5, 1.36.x before 1.36.3, and 1.37.x before 1.37.1 allows for denial of service via a resource consumption method when searching for an extremely long key in a Language Name Search.

Understanding CVE-2021-46149

What is CVE-2021-46149?

This CVE identifies a vulnerability in MediaWiki versions, leading to a denial of service by exploiting the resource consumption through an extended key search in Language Name Search.

The Impact of CVE-2021-46149

The vulnerability enables an attacker to exhaust system resources, causing denial of service and potential disruption of services relying on the affected versions of MediaWiki.

Technical Details of CVE-2021-46149

Vulnerability Description

The issue in MediaWiki versions allows attackers to trigger resource exhaustion by conducting searches for exceptionally long keys in Language Name Search.

Affected Systems and Versions

MediaWiki versions before 1.35.5
MediaWiki 1.36.x versions before 1.36.3
MediaWiki 1.37.x versions before 1.37.1

Exploitation Mechanism

Attackers create searches with exceedingly long keys in the Language Name Search, overwhelming system resources and causing a denial of service condition.

Mitigation and Prevention

Immediate Steps to Take

Update MediaWiki to versions 1.35.5, 1.36.3, or 1.37.1 that contain fixes for this vulnerability.
Ensure access controls are in place to restrict access to the vulnerable functionality.
Monitor system resources for unusual consumption that could indicate an exploitation attempt.

Long-Term Security Practices

Regularly update software to include security patches.
Employ intrusion detection systems to identify unusual activities on the network.

Patching and Updates

Apply patches provided by MediaWiki promptly to mitigate the vulnerability and prevent exploitation.