CVE-2024-1527
📋 TL;DR
This vulnerability allows authenticated users in CMS Made Simple to upload malicious files that bypass security filters, potentially leading to remote code execution via webshells. It affects version 2.2.14 specifically. Organizations using this vulnerable version are at risk of complete system compromise.
💻 Affected Systems
- CMS Made Simple
📦 What is this software?
Cms Made Simple by Cmsmadesimple
⚠️ Risk & Real-World Impact
Worst Case
Full server compromise with attacker gaining persistent access, data exfiltration, and lateral movement within the network.
Likely Case
Unauthorized file upload leading to webshell deployment and limited command execution on the web server.
If Mitigated
File upload attempts logged and blocked by additional security controls, with no successful exploitation.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once credentials are obtained. Public proof-of-concept exists.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.2.15 or later
Vendor Advisory: https://forum.cmsmadesimple.org/viewtopic.php?f=1&t=84685
Restart Required: No
Instructions:
1. Backup your CMS Made Simple installation and database. 2. Download CMS Made Simple 2.2.15 or later from the official website. 3. Replace all files with the new version, preserving your configuration files. 4. Run the upgrade script if prompted. 5. Verify the installation works correctly.
🔧 Temporary Workarounds
Restrict File Upload Extensions
allConfigure web server or application to block upload of executable file types like .php, .phtml, .php5, .php7
# Apache: Add to .htaccess
<FilesMatch "\.(php|phtml|php5|php7)$">
Order Allow,Deny
Deny from all
</FilesMatch>
# Nginx: Add to server block
location ~ \.(php|phtml|php5|php7)$ {
deny all;
}
Disable File Upload Module
allTemporarily disable file upload functionality in CMS Made Simple if not required
# Edit CMS configuration or disable relevant modules in admin panel
🧯 If You Can't Patch
- Implement strict file upload validation at the web application firewall (WAF) level
- Monitor file upload directories for suspicious files and implement file integrity monitoring
🔍 How to Verify
Check if Vulnerable:
Check CMS Made Simple version in admin panel or by examining version.php file in installation directoryCheck Version:
grep '\$CMS_VERSION' /path/to/cms/version.phpVerify Fix Applied:
Confirm version is 2.2.15 or later and test file upload functionality with malicious file attempts📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads to upload directories
- Multiple failed upload attempts followed by successful upload
- Access to suspicious file extensions in web directories
Network Indicators:
- POST requests to file upload endpoints with unusual file types
- Subsequent requests to uploaded files with executable extensions
SIEM Query:
source="web_logs" AND (uri_path="/admin/uploads/" OR uri_path="/uploads/") AND (file_extension="php" OR file_extension="phtml" OR file_extension="php5")