CVE-2019-25422
📋 TL;DR
CVE-2019-25422 is a cross-site scripting vulnerability in Comodo Dome Firewall that allows attackers to inject malicious JavaScript through the vpnfw endpoint. Attackers can execute arbitrary scripts in administrator browsers via reflected XSS in the target parameter or stored XSS in the remark parameter. Organizations using Comodo Dome Firewall 2.7.0 are affected.
💻 Affected Systems
- Comodo Dome Firewall
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could hijack administrator sessions, steal credentials, install backdoors, pivot to internal networks, or completely compromise the firewall management interface.
Likely Case
Attackers would steal administrator credentials or session cookies to gain unauthorized access to the firewall management console, potentially modifying firewall rules or accessing sensitive network information.
If Mitigated
With proper network segmentation and access controls, impact would be limited to the firewall management interface without lateral movement to other systems.
🎯 Exploit Status
Exploit code is publicly available on Exploit-DB (ID 46408), making this easily exploitable by attackers with network access to the management interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.8.0 or later
Vendor Advisory: https://cdome.comodo.com/firewall/
Restart Required: Yes
Instructions:
1. Download the latest version from Comodo's official website. 2. Backup current configuration. 3. Install the update following vendor instructions. 4. Restart the firewall service. 5. Verify the update was successful.
🔧 Temporary Workarounds
Network Access Restriction
allRestrict access to the firewall management interface to trusted IP addresses only
Configure firewall rules to allow management access only from specific IP ranges
Web Application Firewall
allDeploy a WAF in front of the firewall management interface to filter XSS payloads
Configure WAF rules to block requests containing script tags and JavaScript patterns
🧯 If You Can't Patch
- Implement strict network segmentation to isolate the firewall management interface from untrusted networks
- Enable Content Security Policy headers and input validation at network perimeter devices
🔍 How to Verify
Check if Vulnerable:
Check if the firewall version is 2.7.0 via the web interface or CLI. Test by attempting to inject basic XSS payloads into the target and remark parameters of the vpnfw endpoint.Check Version:
ssh admin@firewall-ip 'show version' or check via web interface at /admin/system_infoVerify Fix Applied:
Verify the version is 2.8.0 or later. Test that XSS payloads no longer execute in the browser and are properly sanitized or rejected.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /vpnfw endpoint with script-like content
- Multiple failed login attempts followed by successful login from new IP
- Administrator sessions from unexpected IP addresses or user agents
Network Indicators:
- HTTP requests containing <script> tags or JavaScript functions in POST parameters
- Traffic to the firewall management interface from external IPs
SIEM Query:
source="firewall_logs" AND (uri_path="/vpnfw" AND (http_method="POST" AND (param="target" OR param="remark") AND content="<script>" OR content="javascript:"))