CVE-2019-25415: Comodo Dome Firewall XSS Vulnerability

CVE-2019-25415 Overview

CVE-2019-25415 is a reflected cross-site scripting (XSS) vulnerability affecting Comodo Dome Firewall version 2.7.0. The vulnerability allows attackers to inject malicious scripts by submitting unsanitized input to the hotspot_permanent_users endpoint. Attackers can send POST requests with JavaScript payloads in the MACADDRESSES parameter to execute arbitrary scripts in users' browsers.

Critical Impact

Successful exploitation of this XSS vulnerability could allow attackers to steal session cookies, hijack administrator sessions, redirect users to malicious websites, or perform actions on behalf of authenticated users within the Comodo Dome Firewall administrative interface.

Affected Products

• Comodo Dome Firewall 2.7.0

Discovery Timeline

• 2026-02-19 - CVE CVE-2019-25415 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2019-25415

Vulnerability Analysis

This reflected XSS vulnerability (CWE-79) exists in the Comodo Dome Firewall web management interface. The hotspot_permanent_users endpoint fails to properly sanitize user-supplied input in the MACADDRESSES parameter before reflecting it back in the HTTP response. This allows an attacker to craft malicious URLs or POST requests containing JavaScript code that will execute in the context of a victim's browser session when they interact with the affected endpoint.

The vulnerability is network-accessible, meaning attackers can exploit it remotely without requiring prior authentication. However, successful exploitation requires user interaction—specifically, a victim must click on a malicious link or be tricked into submitting a crafted form.

Root Cause

The root cause of this vulnerability is improper input validation and missing output encoding in the hotspot_permanent_users endpoint. The MACADDRESSES parameter accepts arbitrary user input that is directly reflected in the HTTP response without proper sanitization or HTML entity encoding. This failure to implement secure coding practices for user-controlled input creates the XSS attack surface.

Attack Vector

The attack vector is network-based, requiring an attacker to craft a malicious POST request targeting the hotspot_permanent_users endpoint. The attacker embeds JavaScript payloads within the MACADDRESSES parameter. When an authenticated administrator or user accesses a page containing the reflected payload, the malicious script executes within their browser context.

A typical attack scenario involves the attacker sending a phishing email or embedding a hidden form on a malicious website that automatically submits a POST request to the vulnerable endpoint. When the victim's browser processes the response, the injected JavaScript executes with full access to the victim's session.

For detailed exploitation information, refer to the Exploit-DB #46408 advisory.

Detection Methods for CVE-2019-25415

Indicators of Compromise

• Unusual POST requests to the hotspot_permanent_users endpoint containing <script> tags or JavaScript event handlers in the MACADDRESSES parameter
• HTTP access logs showing encoded JavaScript payloads (e.g., %3Cscript%3E) in request parameters
• Browser-side anomalies such as unexpected redirects or cookie exfiltration attempts originating from the Comodo Dome Firewall management interface

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block requests containing XSS payloads in the MACADDRESSES parameter
• Monitor HTTP logs for POST requests to hotspot_permanent_users containing suspicious characters such as <, >, javascript:, or encoded variants
• Deploy endpoint detection solutions that can identify browser-based script injection attacks targeting administrative interfaces

Monitoring Recommendations

• Enable verbose logging on the Comodo Dome Firewall web interface to capture all requests to management endpoints
• Set up alerting for any requests containing common XSS payload signatures targeting firewall management URLs
• Review authentication logs for suspicious session activity following visits to the affected endpoint

How to Mitigate CVE-2019-25415

Immediate Actions Required

• Restrict access to the Comodo Dome Firewall management interface to trusted IP addresses only
• Implement network segmentation to limit exposure of the firewall administrative interface
• Enable Content Security Policy (CSP) headers if supported to mitigate script execution
• Train administrators to recognize and avoid suspicious links that could trigger the XSS payload

Patch Information

Check with Comodo for the latest firmware updates for Dome Firewall that address this vulnerability. Review the Comodo Firewall Overview page for current product information and security updates. Additionally, consult the VulnCheck Comodo Dome Advisory for detailed remediation guidance.

Workarounds

• Place the Comodo Dome Firewall management interface behind a VPN to limit access to authorized personnel only
• Implement a reverse proxy with WAF capabilities that filters XSS payloads before they reach the vulnerable endpoint
• Configure browser-level protections such as XSS filters and CSP on administrative workstations used to access the firewall interface
• Consider deploying SentinelOne endpoint protection on administrative workstations to detect and block browser-based exploitation attempts

# Example: Restrict management interface access via iptables
# Allow only trusted admin network to access firewall web interface
iptables -A INPUT -p tcp --dport 443 -s 192.168.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP