CVE-2025-6593 Overview
A vulnerability has been identified in Wikimedia Foundation MediaWiki affecting the includes/user/User.php component. This Information Exposure vulnerability (CWE-200) allows unauthorized disclosure of sensitive information through the affected MediaWiki user handling functionality.
Critical Impact
This vulnerability may allow attackers to obtain sensitive user information through the User.php component in MediaWiki installations running vulnerable versions.
Affected Products
- MediaWiki versions from 1.27.0 before 1.39.13
- MediaWiki versions 1.42.7, 1.43.2
- MediaWiki version 1.44.0
Discovery Timeline
- 2026-02-02 - CVE CVE-2025-6593 published to NVD
- 2026-02-04 - Last updated in NVD database
Technical Details for CVE-2025-6593
Vulnerability Analysis
This vulnerability is classified as an Information Exposure issue (CWE-200) affecting the MediaWiki content management system. The vulnerable code resides within the includes/user/User.php file, which handles user-related functionality within MediaWiki installations.
The vulnerability enables unauthorized access to sensitive information that should be protected. In the context of MediaWiki, the User.php component manages user authentication, session handling, and user data retrieval. An information exposure in this component could potentially leak user account details, session information, or other sensitive user-related data to unauthorized parties.
The attack requires network access and some user interaction, making it a targeted attack scenario rather than a mass exploitation vulnerability. The exposure is limited to confidentiality impact without integrity or availability concerns, suggesting the vulnerability allows data leakage but does not permit modification or destruction of data.
Root Cause
The root cause of this vulnerability lies in improper information handling within the includes/user/User.php file. CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor) indicates that the application unintentionally exposes sensitive data through an insecure implementation pattern.
The vulnerability likely stems from inadequate access control checks, improper data sanitization before output, or unintended information disclosure through error messages or API responses within the user handling component.
Attack Vector
The vulnerability is exploitable over a network connection with low attack complexity requirements. However, exploitation requires user interaction and some preconditions must be met for successful exploitation.
An attacker would need to craft a specific request or lure a user into triggering the vulnerable code path in the User.php component. Upon successful exploitation, the attacker can obtain limited confidential information from the target system and potentially from connected systems.
The attack does not require authentication, making it accessible to external threat actors who can reach the MediaWiki installation over the network.
Detection Methods for CVE-2025-6593
Indicators of Compromise
- Unusual access patterns to user-related MediaWiki API endpoints
- Anomalous requests targeting the includes/user/User.php functionality
- Unexpected data exposure in application logs or network traffic
Detection Strategies
- Monitor web application logs for suspicious requests to MediaWiki user endpoints
- Implement web application firewall (WAF) rules to detect information disclosure attack patterns
- Review MediaWiki access logs for enumeration attempts against user data
Monitoring Recommendations
- Enable detailed logging for MediaWiki user-related operations
- Configure alerting for unusual patterns of user data access
- Implement network monitoring to detect potential data exfiltration
How to Mitigate CVE-2025-6593
Immediate Actions Required
- Upgrade MediaWiki to version 1.39.13 or later for the 1.39.x branch
- Review and audit user-related API endpoints for unauthorized access
- Implement additional access controls around the User.php component
Patch Information
Wikimedia Foundation has addressed this vulnerability in MediaWiki version 1.39.13. Organizations running affected versions should upgrade to the patched release. For detailed patch information and the security advisory, refer to the Wikimedia Task T396230.
Workarounds
- Restrict network access to MediaWiki installations using firewall rules
- Implement additional authentication layers for sensitive user operations
- Deploy a web application firewall with rules to filter potentially malicious requests
- Consider temporarily disabling non-essential user-facing features until patching is complete
# Example: Restrict access to MediaWiki installation
# Add to Apache configuration or .htaccess
<Directory "/var/www/html/mediawiki/includes/user">
Require ip 10.0.0.0/8
Require ip 192.168.0.0/16
</Directory>
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
