CVE-2019-17046
📋 TL;DR
CVE-2019-17046 is a critical remote code execution vulnerability in Ilch CMS 2.1.22 that allows attackers to upload malicious PHP files through the media settings interface. This affects all administrators who can access the vulnerable admin page, potentially leading to complete system compromise.
💻 Affected Systems
- Ilch Content Management System
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full server compromise allowing attackers to execute arbitrary commands, steal data, install malware, pivot to other systems, and maintain persistent access.
Likely Case
Webshell deployment leading to data theft, defacement, and further exploitation of the hosting environment.
If Mitigated
Limited impact if proper file upload validation and web application firewalls are in place.
🎯 Exploit Status
Exploitation requires admin credentials but is straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.1.23 and later
Vendor Advisory: https://github.com/IlchCMS/Ilch-2/releases
Restart Required: No
Instructions:
1. Backup your Ilch installation and database. 2. Download Ilch 2.1.23 or later from official repository. 3. Replace all files except config.php and uploads directory. 4. Run update script if available. 5. Verify PHP files are no longer allowed in media uploads.
🔧 Temporary Workarounds
Remove PHP from allowed upload types
allManually modify media settings to disallow PHP file uploads
Edit configuration to remove 'php' from allowed file types in admin/media/settings
Web server file extension blocking
linuxConfigure web server to block execution of uploaded PHP files
For Apache: Add 'RemoveHandler .php' to .htaccess in upload directory
For Nginx: Add 'location ~ \.php$ { deny all; }' to upload directory config
🧯 If You Can't Patch
- Implement strict file upload validation that checks file content, not just extensions
- Restrict admin panel access to trusted IP addresses only
🔍 How to Verify
Check if Vulnerable:
Check if running Ilch 2.1.22 and verify 'php' is listed as allowed file type in admin/media/settingsCheck Version:
Check Ilch version in admin panel or examine version.php fileVerify Fix Applied:
Confirm version is 2.1.23+ and PHP files are rejected when attempting upload📡 Detection & Monitoring
Log Indicators:
- PHP file uploads to media directory
- Admin login attempts followed by file uploads
- Unusual file types in upload directories
Network Indicators:
- POST requests to /admin/media/settings with file upload parameters
- Requests to suspicious PHP files in upload directories
SIEM Query:
web.url:*admin/media* AND (web.method:POST OR file.extension:php)🔗 References
- https://syhack.wordpress.com/2019/09/29/ilch-content-management-system-v-2-1-22-insecure-file-upload-lfi-remote-code-execution-critical-vulnerability-disclosure/
- https://syhack.wordpress.com/2019/09/29/ilch-content-management-system-v-2-1-22-insecure-file-upload-lfi-remote-code-execution-critical-vulnerability-disclosure/
