CVE-2024-34507
📋 TL;DR
This vulnerability allows cross-site scripting (XSS) attacks in MediaWiki due to improper handling of the escape character (0x1b) in comment parsing. Attackers can inject malicious scripts that execute in users' browsers when viewing affected pages. All MediaWiki instances running vulnerable versions are affected.
💻 Affected Systems
- MediaWiki
📦 What is this software?
Fedora by Fedoraproject
Mediawiki by Mediawiki
Mediawiki by Mediawiki
Mediawiki by Mediawiki
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal session cookies, perform actions as authenticated users, deface pages, or redirect users to malicious sites.
Likely Case
Session hijacking, account compromise, or page defacement through script injection in comments or recent changes.
If Mitigated
Limited impact with proper content security policies and input validation, though XSS could still occur.
🎯 Exploit Status
Demonstrated via Special:RecentChanges with crafted URL parameters; simple injection possible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: MediaWiki 1.39.7, 1.40.3, or 1.41.1
Vendor Advisory: https://phabricator.wikimedia.org/T355538
Restart Required: No
Instructions:
1. Backup your MediaWiki installation. 2. Update to the patched version via package manager or manual download. 3. Verify the update applied correctly.
🔧 Temporary Workarounds
Input Sanitization
allFilter or escape the 0x1b character in user input before processing.
Content Security Policy
allImplement strict CSP headers to mitigate XSS impact.
🧯 If You Can't Patch
- Disable or restrict comment functionality if not essential.
- Implement web application firewall rules to block requests containing malicious escape sequences.
🔍 How to Verify
Check if Vulnerable:
Check MediaWiki version via Special:Version page or LocalSettings.php.Check Version:
grep 'wgVersion' LocalSettings.phpVerify Fix Applied:
Confirm version is 1.39.7, 1.40.3, 1.41.1 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual requests to Special:RecentChanges with escape characters
- XSS payloads in comment logs
Network Indicators:
- HTTP requests containing %1b or similar escape sequences
SIEM Query:
source="*mediawiki*" AND (uri="*%1b*" OR user_agent="*<script>*")🔗 References
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY/
- https://phabricator.wikimedia.org/T355538
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FU2FGUXXK6TMV6R52VRECLC6XCSQQISY/
- https://phabricator.wikimedia.org/T355538
