CVE-2023-3767
📋 TL;DR
An OS command injection vulnerability in EasyPHP Webserver 14.1 allows attackers to execute arbitrary commands on the underlying operating system by sending specially crafted requests to the /index.php?zone=settings parameter. This affects all users running the vulnerable version of EasyPHP Webserver, potentially giving attackers full system access.
💻 Affected Systems
- EasyPHP Webserver
📦 What is this software?
Webserver by Easyphp
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to install malware, steal data, pivot to other systems, or establish persistent backdoors.
Likely Case
Remote code execution leading to web server compromise, data exfiltration, and potential lateral movement within the network.
If Mitigated
Limited impact if proper network segmentation, least privilege, and monitoring are in place, though initial compromise is still possible.
🎯 Exploit Status
The vulnerability requires no authentication and has a simple exploitation path via HTTP requests to a specific parameter.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: https://www.incibe.es/incibe-cert/alerta-temprana/avisos/inyeccion-de-comandos-os-en-easyphp-webserver
Restart Required: No
Instructions:
No official patch is available. Consider upgrading to a different web server or implementing workarounds.
🔧 Temporary Workarounds
Disable web interface access
allBlock access to the vulnerable /index.php?zone=settings endpoint
# Configure web server to deny access to /index.php?zone=settings
# Use .htaccess: Deny from all
# Or configure firewall rules to block the path
Network segmentation
allRestrict network access to EasyPHP Webserver administration interface
# Configure firewall to allow access only from trusted IPs
# Example: iptables -A INPUT -p tcp --dport 80 -s trusted_ip -j ACCEPT
# iptables -A INPUT -p tcp --dport 80 -j DROP
🧯 If You Can't Patch
- Immediately isolate the affected system from the internet and critical internal networks
- Implement strict network access controls and monitor all traffic to/from the vulnerable system
🔍 How to Verify
Check if Vulnerable:
Check if EasyPHP Webserver version 14.1 is installed and accessible via HTTP. Test by attempting to access the /index.php?zone=settings endpoint.Check Version:
Check the EasyPHP control panel or installation directory for version informationVerify Fix Applied:
Verify workarounds by testing that the vulnerable endpoint is no longer accessible or that commands cannot be injected.📡 Detection & Monitoring
Log Indicators:
- Unusual POST/GET requests to /index.php?zone=settings with shell metacharacters
- Commands like cmd.exe, powershell, or bash appearing in URL parameters
- Multiple failed exploitation attempts
Network Indicators:
- HTTP requests containing shell commands in the zone parameter
- Outbound connections from the web server to unexpected destinations
SIEM Query:
source="web_server_logs" AND (url="*index.php?zone=settings*" AND (url="*|*" OR url="*;*" OR url="*&*" OR url="*`*"))