CVE-2019-25403: Comodo Dome Firewall XSS Vulnerability

CVE-2019-25403 Overview

CVE-2019-25403 is a stored cross-site scripting (XSS) vulnerability affecting Comodo Dome Firewall version 2.7.0. The vulnerability allows authenticated attackers to inject malicious JavaScript code through the comment parameter in the admin_profiles endpoint. When other users view the affected page, the injected script executes in their browser context, potentially leading to session hijacking, credential theft, or other malicious actions.

Critical Impact

Authenticated attackers can persistently inject malicious scripts that execute in the browsers of other users, including administrators, potentially compromising sensitive firewall management sessions and enabling further attacks on the network infrastructure.

Affected Products

• Comodo Dome Firewall 2.7.0
• Comodo Dome Firewall versions prior to patch release

Discovery Timeline

• 2026-02-19 - CVE CVE-2019-25403 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25403

Vulnerability Analysis

This stored cross-site scripting vulnerability (CWE-79) exists in the administrative interface of Comodo Dome Firewall. The application fails to properly sanitize user-supplied input in the comment parameter when processing requests to the admin_profiles endpoint. Because the malicious payload is stored server-side and rendered without proper encoding, any user who subsequently views the affected administrative page will have the attacker's JavaScript executed in their browser.

The network-accessible attack vector means the vulnerability can be exploited remotely by any authenticated user with access to the firewall's management interface. The stored nature of this XSS variant makes it particularly dangerous as it persists across sessions and can affect multiple victims without requiring additional attacker interaction.

Root Cause

The root cause is improper input validation and output encoding in the Comodo Dome Firewall administrative interface. When user input is submitted through the comment parameter, the application stores the data without sanitizing HTML or JavaScript content. Upon rendering the page containing the comment, the application outputs the stored data directly into the HTML document without proper encoding, allowing embedded scripts to execute in the victim's browser context.

Attack Vector

An authenticated attacker exploits this vulnerability by navigating to the admin_profiles endpoint and submitting a crafted payload containing malicious JavaScript in the comment parameter. The malicious script is stored in the application database. When another user, such as an administrator, views the page containing the attacker's comment, the JavaScript executes in their browser with the privileges of that user's session. This can enable session hijacking, privilege escalation, or further attacks against the firewall infrastructure.

For detailed technical information regarding the exploitation methodology, refer to the Exploit-DB #46408 entry or the VulnCheck Comodo Advisory.

Detection Methods for CVE-2019-25403

Indicators of Compromise

• Unusual JavaScript payloads or HTML tags appearing in comment fields within the admin_profiles endpoint
• Unexpected outbound connections from administrator browsers to unknown external domains
• Session tokens or credentials being transmitted to unauthorized endpoints
• Modified or suspicious entries in application logs related to the admin_profiles functionality

Detection Strategies

• Implement web application firewall (WAF) rules to detect and block XSS payloads in form submissions
• Monitor HTTP traffic for suspicious script tags and JavaScript event handlers in POST parameters
• Review stored data in the firewall's database for unexpected HTML or JavaScript content
• Enable Content Security Policy (CSP) headers to detect and report inline script execution attempts

Monitoring Recommendations

• Configure logging for all administrative interface access and form submissions
• Set up alerts for anomalous browser behavior patterns from administrator workstations
• Implement integrity monitoring on stored comment data to detect unauthorized modifications
• Deploy endpoint detection and response (EDR) solutions to identify potential post-exploitation activity

How to Mitigate CVE-2019-25403

Immediate Actions Required

• Restrict access to the Comodo Dome Firewall administrative interface to trusted networks only
• Implement additional input validation at the network perimeter using a WAF
• Review existing stored comments for malicious content and remove any suspicious entries
• Enable Content Security Policy headers to mitigate the impact of any existing XSS payloads

Patch Information

Organizations should check with Comodo for security updates addressing this vulnerability. Review the Comodo Firewall Overview page for product information and potential patch availability. Until a patch is applied, implement the recommended workarounds to reduce risk exposure.

Workarounds

• Limit administrative interface access to specific trusted IP addresses or VPN connections
• Implement a reverse proxy with XSS filtering capabilities in front of the firewall management interface
• Deploy browser-based XSS protection extensions for administrators accessing the interface
• Regularly audit stored content in the admin_profiles section for malicious payloads

# Example: Restrict admin interface access via network firewall rules
# Allow only trusted management network to access firewall admin interface
iptables -A INPUT -p tcp --dport 443 -s 10.0.100.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP