CVE-2020-20672
📋 TL;DR
KiteCMS V1.1 contains an arbitrary file upload vulnerability in the /admin/upload/uploadfile endpoint that allows attackers to upload malicious PHP files. This enables remote code execution (RCE) and complete system compromise. Any organization running KiteCMS V1.1 with the vulnerable upload functionality accessible is affected.
💻 Affected Systems
- KiteCMS
📦 What is this software?
Kitecms by Kitesky
⚠️ Risk & Real-World Impact
Worst Case
Complete server takeover with attacker gaining shell access, installing backdoors, stealing data, and pivoting to other systems.
Likely Case
Webshell deployment leading to data exfiltration, defacement, or use as part of a botnet.
If Mitigated
Attack blocked at web application firewall level or file upload validation prevents malicious files.
🎯 Exploit Status
Exploitation requires access to the upload endpoint, which may require authentication. The vulnerability is simple to exploit once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: No official vendor advisory found
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a newer version if available, or implement workarounds.
🔧 Temporary Workarounds
Restrict file upload types
allConfigure web server or application to only allow specific safe file extensions (e.g., .jpg, .png) and validate file content.
# Example Apache .htaccess to block PHP uploads
<FilesMatch "\.(php|php3|php4|php5|phtml|pl|cgi|asp|aspx)">
Order Deny,Allow
Deny from all
</FilesMatch>
Disable vulnerable endpoint
allBlock access to /admin/upload/uploadfile via web server configuration or application routing.
# Example Nginx location block
location /admin/upload/uploadfile {
deny all;
return 403;
}
🧯 If You Can't Patch
- Implement strict file upload validation including whitelisting allowed extensions, checking MIME types, and scanning uploaded files.
- Deploy a web application firewall (WAF) with rules to detect and block malicious file upload attempts.
🔍 How to Verify
Check if Vulnerable:
Attempt to upload a PHP file to /admin/upload/uploadfile endpoint. If successful without proper validation, the system is vulnerable.Check Version:
Check KiteCMS version in admin panel or configuration files. Look for version 1.1 in source code or documentation.Verify Fix Applied:
Test file upload with PHP extension; it should be rejected. Verify WAF rules or configuration changes are active.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /admin/upload/uploadfile with PHP file uploads
- Unusual file creation in upload directories with .php extension
Network Indicators:
- POST requests to upload endpoint with PHP file content in payloads
SIEM Query:
source="web_logs" AND url="/admin/upload/uploadfile" AND method="POST" AND (file_extension="php" OR content_type="application/x-php")