CVE-2025-53501
📋 TL;DR
An improper access control vulnerability in the MediaWiki Scribunto extension allows unauthorized users to execute functions that should be restricted. This affects MediaWiki installations with the Scribunto extension enabled, specifically versions 1.39.X before 1.39.12, 1.42.X before 1.42.7, and 1.43.X before 1.43.2.
💻 Affected Systems
- MediaWiki with Scribunto Extension
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could execute arbitrary Lua code with elevated privileges, potentially leading to data manipulation, information disclosure, or server compromise.
Likely Case
Unauthorized users could access restricted functionality, modify content they shouldn't have access to, or extract sensitive information from the wiki.
If Mitigated
With proper access controls and network segmentation, impact would be limited to the specific MediaWiki instance without lateral movement.
🎯 Exploit Status
Exploitation requires some understanding of MediaWiki's Lua scripting environment and access control mechanisms.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.39.12, 1.42.7, or 1.43.2
Vendor Advisory: https://phabricator.wikimedia.org/T397524
Restart Required: No
Instructions:
1. Identify your MediaWiki version. 2. Upgrade to the patched version for your branch: 1.39.12, 1.42.7, or 1.43.2. 3. Verify the Scribunto extension is updated as part of the MediaWiki update.
🔧 Temporary Workarounds
Disable Scribunto Extension
allTemporarily disable the vulnerable Scribunto extension if immediate patching isn't possible.
Edit LocalSettings.php and add: wfLoadExtension('Scribunto'); // Comment or remove this line
Restrict User Permissions
allTighten user permissions to limit who can edit pages with Scribunto modules.
Edit LocalSettings.php to adjust $wgGroupPermissions for editing and module creation
🧯 If You Can't Patch
- Implement strict network access controls to limit who can access the MediaWiki instance
- Enable detailed logging and monitoring for suspicious Lua module executions
🔍 How to Verify
Check if Vulnerable:
Check MediaWiki version and Scribunto extension status in Special:Version pageCheck Version:
Check LocalSettings.php or visit Special:Version in your MediaWiki installationVerify Fix Applied:
Confirm MediaWiki version is 1.39.12, 1.42.7, or 1.43.2 or higher in Special:Version📡 Detection & Monitoring
Log Indicators:
- Unusual Lua module executions
- Unauthorized edit attempts to Scribunto modules
- Access to restricted functions in Lua scripts
Network Indicators:
- Unusual patterns of requests to Scribunto-related endpoints
SIEM Query:
Search for 'Scribunto' or 'Lua' in MediaWiki logs with unauthorized user IDs or unusual frequency