CVE-2025-61658 Overview
A vulnerability has been identified in Wikimedia Foundation CheckUser extension. This vulnerability is associated with program files src/GlobalContributions/GlobalContributionsPager.php. The flaw affects CheckUser versions before 1.43.4 and 1.44.1, potentially allowing authenticated users with network access to extract limited confidential information.
Critical Impact
Authenticated attackers may exploit this vulnerability to gain unauthorized access to limited confidential information through the GlobalContributionsPager component.
Affected Products
- Wikimedia Foundation CheckUser versions before 1.43.4
- Wikimedia Foundation CheckUser version 1.44.0 (before 1.44.1)
Discovery Timeline
- 2026-02-03 - CVE CVE-2025-61658 published to NVD
- 2026-02-03 - Last updated in NVD database
Technical Details for CVE-2025-61658
Vulnerability Analysis
This vulnerability exists within the CheckUser extension for MediaWiki, specifically in the GlobalContributionsPager.php file located in the src/GlobalContributions/ directory. The CheckUser extension is a critical tool used by Wikipedia and other Wikimedia projects to allow authorized users to check IP addresses and other information about editors for anti-vandalism and sockpuppet investigation purposes.
The vulnerability allows an authenticated attacker with network access to potentially extract limited confidential information. Given that CheckUser handles sensitive user data including IP addresses and editing patterns, even a low-impact information disclosure could compromise user privacy on Wikimedia projects.
Root Cause
The root cause appears to be an information disclosure issue within the GlobalContributionsPager.php component. This pager class handles the display of global contributions across Wikimedia wikis, and the vulnerability likely stems from improper access controls or data filtering that could expose information to users who should not have access to it.
Attack Vector
The attack requires network access and authentication (low privileges). An attacker would need to:
- Obtain valid credentials for a Wikimedia wiki running the vulnerable CheckUser extension
- Craft specific requests targeting the GlobalContributionsPager functionality
- Extract limited confidential information that should be restricted
The vulnerability does not require user interaction and can be exploited remotely over the network. For detailed technical information about this vulnerability, refer to the Wikimedia Task T404805.
Detection Methods for CVE-2025-61658
Indicators of Compromise
- Unusual access patterns to GlobalContributions endpoints by low-privileged users
- Unexpected queries or requests targeting GlobalContributionsPager.php functionality
- Anomalous data access logs showing users viewing information beyond their authorization level
Detection Strategies
- Monitor web server logs for abnormal request patterns to CheckUser extension endpoints
- Implement auditing for GlobalContributions page access and track user permission levels
- Review MediaWiki access logs for suspicious activity targeting the CheckUser extension
Monitoring Recommendations
- Enable verbose logging for the CheckUser extension to capture detailed access information
- Set up alerts for repeated requests to GlobalContributions functionality from single users
- Periodically audit user access patterns to CheckUser-related features
How to Mitigate CVE-2025-61658
Immediate Actions Required
- Update CheckUser extension to version 1.43.4 or later for the 1.43.x branch
- Update CheckUser extension to version 1.44.1 or later for the 1.44.x branch
- Review CheckUser access logs for any signs of exploitation
- Audit user permissions to ensure only authorized personnel have access to CheckUser functionality
Patch Information
Wikimedia Foundation has addressed this vulnerability in CheckUser versions 1.43.4 and 1.44.1. Administrators should update their MediaWiki installations with the patched extension versions as soon as possible. For additional details, consult the Wikimedia Task T404805.
Workarounds
- Temporarily restrict access to the CheckUser extension to only essential administrators
- Implement additional authentication requirements for accessing GlobalContributions functionality
- Consider disabling the GlobalContributions feature if not actively needed until patches can be applied
- Monitor and log all CheckUser extension access while awaiting updates
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
