CVE-2025-69581
📋 TL;DR
Chamilo LMS 1.11.2 fails to properly clear cached sensitive user data from the Social Network/personal_data endpoint after logout. This allows subsequent users of the same device to access previous users' personal information via browser back button or cache restoration, affecting all users of vulnerable Chamilo LMS instances.
💻 Affected Systems
- Chamilo LMS
📦 What is this software?
Chamilo Lms by Chamilo
⚠️ Risk & Real-World Impact
Worst Case
Malicious actors on shared devices could access complete personal profiles, enabling identity theft, targeted phishing campaigns, or impersonation attacks against users.
Likely Case
Accidental exposure of personal data to subsequent users on shared computers or public terminals, leading to privacy violations and potential harassment.
If Mitigated
With proper cache-control headers and session management, no sensitive data persists after logout, eliminating the information disclosure risk.
🎯 Exploit Status
Exploitation requires physical or remote access to a device where a user previously logged into a vulnerable Chamilo instance. No authentication needed for the cached data access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not yet released
Vendor Advisory: https://github.com/chamilo/chamilo-lms
Restart Required: No
Instructions:
1. Monitor Chamilo security advisories for patch release
2. Apply patch when available
3. Clear application cache after patching
🔧 Temporary Workarounds
Add Cache-Control Headers
allManually implement proper cache-control headers for the /personal_data endpoint to prevent browser caching
Add to application configuration or .htaccess: Cache-Control: no-store, no-cache, must-revalidate, max-age=0
Session Management Enhancement
allImplement server-side session invalidation on logout to clear all user data
Modify logout function to destroy session and clear user-specific cache
🧯 If You Can't Patch
- Implement mandatory logout timeout policies and educate users to manually clear browser cache after using shared devices
- Deploy web application firewall rules to strip caching headers from sensitive endpoints
🔍 How to Verify
Check if Vulnerable:
1. Log into Chamilo LMS 1.11.2
2. Access Social Network/personal_data
3. Log out
4. Use browser back button - if personal data appears, system is vulnerableCheck Version:
Check Chamilo version in admin panel or via CHAMILO_VERSION constantVerify Fix Applied:
Repeat verification steps after applying fix - personal data should not be accessible after logout📡 Detection & Monitoring
Log Indicators:
- Multiple user sessions from same IP accessing /personal_data endpoint in quick succession
- Unauthorized access attempts to cached user data
Network Indicators:
- Missing Cache-Control headers in HTTP responses for sensitive endpoints
- Browser caching directives present on personal data responses
SIEM Query:
source="web_server" AND (uri="/personal_data" OR uri="/social/personal_data") AND status=200 AND cache-control=""