CVE-2024-58280
📋 TL;DR
CMSimple 5.15 contains a remote command execution vulnerability where authenticated attackers can modify file extension settings to upload malicious PHP files. This allows execution of arbitrary code on the server. All CMSimple 5.15 installations with authenticated user access are affected.
💻 Affected Systems
- CMSimple
📦 What is this software?
Cmsimple by Cmsimple
⚠️ Risk & Real-World Impact
Worst Case
Full server compromise leading to data theft, ransomware deployment, or complete system takeover
Likely Case
Webshell installation enabling persistent backdoor access, data exfiltration, and lateral movement
If Mitigated
Limited impact if proper file upload restrictions and user access controls are implemented
🎯 Exploit Status
Exploit requires authenticated access but is straightforward to execute
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available; upgrade to a newer version if available or implement workarounds
🔧 Temporary Workarounds
Restrict file upload extensions
allModify CMSimple configuration to restrict allowed file extensions and prevent PHP file uploads
Edit config.php or relevant configuration files to remove 'php' from allowed extensions
Web server file type restrictions
allConfigure web server to block execution of PHP files in upload directories
For Apache: Add 'php_flag engine off' to .htaccess in media directory
For Nginx: Add 'location ~ \.php$ { deny all; }' to server block
🧯 If You Can't Patch
- Restrict authenticated user access to minimum required permissions
- Implement web application firewall rules to block suspicious file upload patterns
🔍 How to Verify
Check if Vulnerable:
Check if running CMSimple 5.15 and verify if PHP files can be uploaded to media directoryCheck Version:
Check CMSimple version in admin panel or version.php fileVerify Fix Applied:
Attempt to upload a PHP file to media directory; should be blocked or not execute📡 Detection & Monitoring
Log Indicators:
- File uploads with .php extension to media directory
- Configuration changes to Extensions_userfiles
- Unusual authenticated user activity
Network Indicators:
- POST requests to file upload endpoints with PHP content
- HTTP requests to newly uploaded PHP files
SIEM Query:
source="web_logs" AND (uri="*upload*" AND file_extension="php") OR (uri="*/media/*.php")