CVE-2019-25411: Comodo Dome Firewall XSS Vulnerability

CVE-2019-25411 Overview

Comodo Dome Firewall 2.7.0 contains a reflected cross-site scripting (XSS) vulnerability that allows attackers to inject malicious scripts by manipulating the GATEWAY_GREEN parameter. Attackers can send POST requests to the DHCP configuration endpoint with script payloads to execute arbitrary JavaScript in administrator browsers, potentially leading to session hijacking, credential theft, or unauthorized administrative actions.

Critical Impact

Successful exploitation enables attackers to execute arbitrary JavaScript in the context of authenticated administrator sessions, potentially compromising firewall management and network security configurations.

Affected Products

• Comodo Dome Firewall 2.7.0

Discovery Timeline

• 2026-02-19 - CVE CVE-2019-25411 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25411

Vulnerability Analysis

This reflected cross-site scripting vulnerability (CWE-79) exists within the DHCP configuration interface of Comodo Dome Firewall 2.7.0. The vulnerability stems from insufficient input validation and output encoding when processing the GATEWAY_GREEN parameter in POST requests to the DHCP configuration endpoint.

When an administrator interacts with a maliciously crafted request, the injected script payload is reflected back in the HTTP response without proper sanitization. This allows the attacker-controlled JavaScript to execute within the security context of the administrator's browser session, giving the attacker the ability to perform actions on behalf of the authenticated user.

The network-based attack vector requires user interaction, as the victim must click on a malicious link or submit a crafted form. However, once triggered, the impact can be significant given the administrative nature of the targeted interface.

Root Cause

The root cause of this vulnerability is improper neutralization of user-supplied input before it is included in web page output. The GATEWAY_GREEN parameter value is not adequately sanitized or encoded when reflected in the DHCP configuration response, allowing HTML and JavaScript code to be interpreted by the victim's browser rather than being treated as plain text data.

Attack Vector

The attack is conducted over the network and requires an attacker to craft a malicious POST request targeting the DHCP configuration endpoint. The attacker must then socially engineer an authenticated administrator to execute this request, typically through phishing techniques such as:

• Embedding a malicious form submission in an email or web page
• Sending a link that triggers an automatic POST request via JavaScript
• Exploiting another vulnerability to chain with this XSS

Once the administrator's browser processes the malicious request, the injected JavaScript executes with the privileges of the administrator session, potentially allowing the attacker to steal session cookies, modify firewall configurations, or create new administrative accounts.

Detection Methods for CVE-2019-25411

Indicators of Compromise

• Unusual POST requests to DHCP configuration endpoints containing script tags or JavaScript event handlers
• HTTP logs showing GATEWAY_GREEN parameter values with encoded or plaintext <script> tags
• Browser console errors indicating blocked or executed inline scripts from unexpected sources
• Session anomalies following administrator access to DHCP configuration pages

Detection Strategies

• Implement web application firewall (WAF) rules to detect XSS patterns in POST parameters targeting DHCP endpoints
• Configure intrusion detection systems to alert on common XSS payload signatures in HTTP traffic
• Enable detailed logging for the firewall management interface and monitor for suspicious parameter values
• Deploy endpoint detection solutions to identify browser-based script injection attempts

Monitoring Recommendations

• Monitor administrator session activity for unusual actions following access to DHCP configuration pages
• Review HTTP access logs for POST requests to DHCP endpoints with suspicious parameter content
• Set up alerts for multiple failed or unusual authentication attempts following XSS indicator detection
• Implement Content Security Policy violation reporting to detect script injection attempts

How to Mitigate CVE-2019-25411

Immediate Actions Required

• Restrict network access to the Comodo Dome Firewall management interface to trusted IP addresses only
• Implement additional network segmentation to isolate the firewall management console
• Educate administrators about the risks of clicking on untrusted links while authenticated to the firewall interface
• Consider implementing a web application firewall (WAF) in front of the management interface to filter XSS payloads

Patch Information

Consult the Comodo Firewall product page for information on updated firmware versions that address this vulnerability. Review the VulnCheck Comodo XSS Advisory for additional technical details and remediation guidance.

Technical details regarding this vulnerability are available at Exploit-DB #46408.

Workarounds

• Implement strict network access controls limiting management interface access to specific administrator workstations
• Use a dedicated, isolated browser profile exclusively for firewall administration tasks
• Enable Content Security Policy (CSP) headers if configurable to restrict inline script execution
• Deploy browser-based XSS protection extensions on administrator workstations as an additional defense layer