CVE-2020-19527
📋 TL;DR
CVE-2020-19527 is a critical OS command injection vulnerability in iCMS 7.0.14 that allows attackers to execute arbitrary commands on the server by injecting shell metacharacters into the DB_NAME parameter during installation. This affects all iCMS 7.0.14 installations that haven't been patched or properly secured.
💻 Affected Systems
- iCMS
📦 What is this software?
Icms by Idreamsoft
⚠️ Risk & Real-World Impact
Worst Case
Full server compromise leading to data theft, ransomware deployment, lateral movement to other systems, and complete system takeover.
Likely Case
Attackers gain shell access to the web server, install backdoors, steal sensitive data, and potentially pivot to other systems on the network.
If Mitigated
Limited impact with proper network segmentation, minimal privileges, and intrusion detection systems in place.
🎯 Exploit Status
Simple command injection via HTTP parameter manipulation. No authentication required during installation phase.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.0.15 and later
Vendor Advisory: https://github.com/idreamsoft/iCMS/issues/66
Restart Required: No
Instructions:
1. Upgrade to iCMS 7.0.15 or later. 2. Remove the install/ directory after installation. 3. Verify the fix by checking version and testing parameter sanitization.
🔧 Temporary Workarounds
Remove installation directory
linuxDelete the install/ directory after successful installation to prevent access to vulnerable endpoint
rm -rf /path/to/icms/install/
Input validation via WAF
allImplement web application firewall rules to block shell metacharacters in DB_NAME parameter
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user inputs
- Deploy network segmentation and restrict access to installation endpoints
🔍 How to Verify
Check if Vulnerable:
Check if install/install.php exists and test DB_NAME parameter with shell metacharacters like ; or |Check Version:
Check iCMS configuration files or admin panel for version informationVerify Fix Applied:
Verify version is 7.0.15+ and test that shell metacharacters in DB_NAME are properly sanitized📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to install/install.php with shell metacharacters
- Unexpected system command execution from web server user
Network Indicators:
- HTTP requests containing shell metacharacters in parameters
- Outbound connections from web server to unusual destinations
SIEM Query:
source="web_logs" AND uri="/install/install.php" AND (param="DB_NAME" AND value MATCHES "[;|&`$()]+")