CVE-2019-25423: Comodo Dome Firewall XSS Vulnerability

CVE-2019-25423 Overview

CVE-2019-25423 is a reflected Cross-Site Scripting (XSS) vulnerability affecting Comodo Dome Firewall 2.7.0. The vulnerability exists in the /korugan/proxyconfig endpoint, where multiple POST parameters fail to properly sanitize user input before reflecting it back in the response. This allows attackers to inject malicious JavaScript code that executes in the context of an administrator's browser session.

Critical Impact

Attackers can execute arbitrary JavaScript in administrator browsers, potentially leading to session hijacking, credential theft, or administrative actions performed on behalf of compromised users.

Affected Products

• Comodo Dome Firewall 2.7.0

Discovery Timeline

• 2026-02-19 - CVE CVE-2019-25423 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25423

Vulnerability Analysis

This vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), commonly known as Cross-Site Scripting. The Comodo Dome Firewall web management interface fails to properly validate and sanitize user-supplied input in the proxy configuration endpoint. When an administrator processes a crafted request containing malicious JavaScript payloads, the script executes within their authenticated browser session.

The vulnerability requires user interaction, as an administrator must be tricked into submitting or viewing a maliciously crafted request. However, once triggered, the attacker gains the ability to perform actions with the privileges of the authenticated administrator, potentially compromising the entire firewall configuration.

Root Cause

The root cause of this vulnerability is insufficient input validation and output encoding in the /korugan/proxyconfig endpoint. The application directly reflects user-supplied POST parameters back to the browser without proper sanitization or HTML entity encoding. Specifically, parameters including PROXY_PORT, VISIBLE_HOSTNAME, ADMIN_MAIL_ADDRESS, CACHE_MEM, MAX_SIZE, MIN_SIZE, and DST_NOCACHE are vulnerable to script injection.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker crafts a malicious POST request containing JavaScript payloads in one or more of the vulnerable parameters. The attacker then tricks an authenticated administrator into submitting this request, typically through social engineering tactics such as phishing emails or malicious links.

When the administrator's browser processes the response from the /korugan/proxyconfig endpoint, the injected JavaScript executes with the administrator's session privileges. This can enable session token theft, keylogging, modification of firewall rules, or redirection to attacker-controlled sites.

Technical details and proof-of-concept information can be found in the Exploit-DB entry #46408 and the VulnCheck Advisory on Comodo Dome.

Detection Methods for CVE-2019-25423

Indicators of Compromise

• Unexpected JavaScript tags or encoded script content in web server access logs for the /korugan/proxyconfig endpoint
• POST requests containing script injection patterns such as <script>, javascript:, or encoded variants in proxy configuration parameters
• Unusual administrative session activity following access to proxy configuration pages

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block XSS payloads in POST parameters targeting the /korugan/proxyconfig endpoint
• Monitor HTTP request logs for suspicious patterns including script tags, event handlers (e.g., onerror, onload), and JavaScript URIs
• Deploy browser-based security controls such as Content Security Policy (CSP) headers to prevent inline script execution

Monitoring Recommendations

• Enable detailed logging for all administrative interface access and review logs for anomalous parameter values
• Configure alerting for any requests to proxy configuration endpoints containing HTML or JavaScript syntax
• Implement session monitoring to detect suspicious administrative actions that may indicate account compromise

How to Mitigate CVE-2019-25423

Immediate Actions Required

• Restrict administrative interface access to trusted networks and IP addresses only
• Implement Content Security Policy (CSP) headers to mitigate the impact of successful XSS attacks
• Educate administrators about phishing attacks and the risks of clicking untrusted links while authenticated to management interfaces
• Deploy a web application firewall with XSS detection capabilities in front of the Comodo Dome Firewall management interface

Patch Information

No vendor patch information is currently available in the CVE data. Organizations should contact Comodo directly for the latest security updates or consider upgrading to a newer version of Comodo Dome Firewall if available. Additional information about the product can be found on the Comodo Firewall Overview page.

Workarounds

• Limit access to the Comodo Dome Firewall administrative interface to a dedicated management network isolated from general user traffic
• Use a separate browser profile or incognito mode exclusively for firewall administration to limit the impact of session hijacking
• Implement network-level access controls to ensure only authorized administrator workstations can reach the management interface
• Consider placing a reverse proxy with XSS filtering capabilities in front of the management interface as an additional layer of defense

# Example: Restrict management interface access via iptables
iptables -A INPUT -p tcp --dport 443 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP