CVE-2023-44973
📋 TL;DR
This vulnerability allows attackers to upload arbitrary PHP files to Emlog Pro's template directory, leading to remote code execution. It affects Emlog Pro v2.2.0 installations with the vulnerable component accessible. Attackers can gain complete control of affected systems.
💻 Affected Systems
- Emlog Pro
📦 What is this software?
Emlog by Emlog
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining root/admin privileges, data exfiltration, ransomware deployment, and persistent backdoor installation.
Likely Case
Web server compromise leading to website defacement, data theft, and use as pivot point for internal network attacks.
If Mitigated
Attack blocked at web application firewall level with no file uploads reaching vulnerable component.
🎯 Exploit Status
Public exploit code available on GitHub demonstrates simple file upload to achieve RCE.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch available. Check Emlog Pro website or repository for security updates. Consider upgrading to latest version if available.
🔧 Temporary Workarounds
Restrict template directory access
allBlock direct access to /content/templates/ directory via web server configuration
# Apache: Add to .htaccess in web root
<Directory /path/to/content/templates>
Order deny,allow
Deny from all
</Directory>
# Nginx: Add to server block
location ~ ^/content/templates/ {
deny all;
return 403;
}
File upload validation
allImplement server-side file type validation for template uploads
# PHP example to validate file extensions
$allowed_extensions = ['zip', 'tar', 'gz'];
$file_extension = strtolower(pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION));
if (!in_array($file_extension, $allowed_extensions)) {
die('Invalid file type');
}
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block requests containing .php files to /content/templates/
- Disable template upload functionality entirely if not required for operations
🔍 How to Verify
Check if Vulnerable:
Attempt to upload a test PHP file to /content/templates/ via web interface or direct POST request. If upload succeeds and file is accessible via URL, system is vulnerable.Check Version:
Check Emlog Pro admin panel or examine version.php file in installation directoryVerify Fix Applied:
Attempt same upload test after applying workarounds. Upload should be blocked or file should not be executable.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /content/templates/ with .php file uploads
- Web server logs showing successful uploads (HTTP 200) to template directory
- Execution of unexpected PHP files from template directory
Network Indicators:
- Unusual outbound connections from web server following template uploads
- POST requests with file uploads to vulnerable endpoint
SIEM Query:
source="web_server_logs" AND (uri="/content/templates/" AND method="POST" AND (file_extension=".php" OR content_type="application/x-php"))