CVE-2025-11346
📋 TL;DR
This CVE describes a remote deserialization vulnerability in ILIAS learning management systems. Attackers can exploit the Base64 Decoding Handler's unserialize function by manipulating the f_settings parameter to execute arbitrary code. All ILIAS installations up to versions 8.23, 9.13, and 10.1 are affected.
💻 Affected Systems
- ILIAS Learning Management System
📦 What is this software?
Ilias by Ilias
Ilias by Ilias
Ilias by Ilias
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, data theft, and lateral movement within the network.
Likely Case
Remote code execution allowing attackers to gain unauthorized access, modify content, or disrupt the learning management system.
If Mitigated
Limited impact with proper network segmentation and application firewalls blocking malicious payloads.
🎯 Exploit Status
The vulnerability is remotely exploitable without authentication and has public technical details available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.24, 9.14, and 10.2
Vendor Advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2025-2113
Restart Required: Yes
Instructions:
1. Backup your ILIAS installation and database. 2. Download the patched version from the official ILIAS repository. 3. Replace the affected files with the patched versions. 4. Restart the web server service. 5. Verify the update was successful.
🔧 Temporary Workarounds
Input Validation Filter
allImplement strict input validation for the f_settings parameter to block malicious payloads.
# Add input validation in the affected PHP files
# Example: if (!preg_match('/^[a-zA-Z0-9\/+=]+$/', $f_settings)) { die('Invalid input'); }
Web Application Firewall Rule
allConfigure WAF to block requests containing serialized PHP objects in the f_settings parameter.
# ModSecurity rule example: SecRule ARGS:f_settings "@rx (O:\d+:|C:\d+:|a:\d+:)" "id:1001,phase:2,deny,status:403,msg:'PHP deserialization attempt'
🧯 If You Can't Patch
- Implement strict network segmentation to isolate ILIAS servers from critical systems.
- Deploy a web application firewall with rules specifically targeting PHP deserialization attacks.
🔍 How to Verify
Check if Vulnerable:
Check the ILIAS version in the administration panel or by examining the version.php file in the installation directory.Check Version:
grep -r "\$ilias_version" /path/to/ilias/version.phpVerify Fix Applied:
Verify the version number shows 8.24, 9.14, or 10.2 or higher in the administration interface.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to ILIAS endpoints with base64-encoded f_settings parameters
- PHP error logs showing unserialize() warnings or errors
Network Indicators:
- HTTP requests containing serialized PHP object patterns in parameters
- Unexpected outbound connections from ILIAS servers
SIEM Query:
source="web_logs" AND uri="*ilias*" AND (param="f_settings" OR body="O:*" OR body="C:*")