CVE-2024-45612
📋 TL;DR
This vulnerability allows untrusted users to inject Contao insert tags into canonical URL tags, which are then processed and rendered on the front-end web pages. It affects Contao CMS users running vulnerable versions. The injection occurs through canonical tag manipulation.
💻 Affected Systems
- Contao CMS
📦 What is this software?
Contao by Contao
Contao by Contao
Contao by Contao
⚠️ Risk & Real-World Impact
Worst Case
Attackers could inject malicious insert tags that execute arbitrary code, potentially leading to remote code execution, data theft, or website defacement.
Likely Case
Attackers inject malicious content into canonical tags that gets rendered on web pages, potentially enabling cross-site scripting (XSS), content manipulation, or SEO poisoning.
If Mitigated
With proper input validation and output encoding, the impact is limited to minor content manipulation without code execution.
🎯 Exploit Status
Exploitation requires user input in canonical tags, which are processed by the front-end rendering engine.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Contao 4.13.49, 5.3.15, or 5.4.3
Vendor Advisory: https://contao.org/en/security-advisories/insert-tag-injection-via-canonical-urls
Restart Required: No
Instructions:
1. Backup your Contao installation and database. 2. Update Contao to version 4.13.49, 5.3.15, or 5.4.3 using Composer or the Contao Manager. 3. Clear the cache after update.
🔧 Temporary Workarounds
Disable canonical tags
allDisable canonical tags in root page settings to prevent injection
Navigate to Contao backend > Page structure > Root page > Settings > Disable 'Canonical link'
🧯 If You Can't Patch
- Disable canonical tags in all root page settings immediately
- Implement web application firewall rules to block insert tag patterns in canonical URLs
🔍 How to Verify
Check if Vulnerable:
Check Contao version in backend or via composer show contao/contaoCheck Version:
composer show contao/contao | grep versionVerify Fix Applied:
Verify version is 4.13.49, 5.3.15, or 5.4.3 or higher📡 Detection & Monitoring
Log Indicators:
- Unusual insert tag patterns in canonical URLs
- Multiple failed canonical URL submissions
Network Indicators:
- HTTP requests with malicious insert tags in canonical parameters
SIEM Query:
web_requests WHERE url CONTAINS 'canonical' AND (url CONTAINS '{{' OR url CONTAINS '}}')