CVE-2025-6947 in Fireware OS
Summary
by MITRE • 09/16/2025
A stored cross-site scripting (XSS) vulnerability exists in the management interface of WatchGuard Firebox appliances via the SIP Proxy configuration. An authenticated remote attacker with administrator privileges could exploit this vulnerability to execute arbitrary JavaScript code in the Firebox management interface of another management user.
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Analysis
by VulDB Data Team • 08/08/2026
The vulnerability identified as CVE-2025-6947 represents a critical cross-site scripting flaw within the WatchGuard Fireware OS operating system, specifically impacting the SIP Proxy module functionality. This weakness falls under the category of improper input neutralization during web page generation, creating a persistent security risk that can be exploited through stored cross-site scripting techniques. The vulnerability's classification aligns with CWE-79, which defines cross-site scripting as a common web application security flaw occurring when applications fail to properly sanitize user-supplied data before incorporating it into dynamic web content. The attack vector requires an authenticated administrator session to a locally managed Firebox device, indicating that the threat is not externally exploitable but rather relies on compromised administrative credentials or insider threats.
The technical implementation of this vulnerability stems from insufficient validation and sanitization of input parameters within the SIP Proxy module's web interface. When administrators interact with the system through the web management console, maliciously crafted input data can be stored within the application's database or configuration files, subsequently executed when other users access the affected web pages. This stored XSS mechanism allows attackers to inject malicious scripts that persist beyond the initial request, making the vulnerability particularly dangerous as it can affect multiple users over extended periods. The affected Firebox versions span from 12.0 through 12.11.2, indicating a significant timeframe of impacted releases that would require comprehensive patch management across organizations relying on these security appliances.
The operational impact of this vulnerability extends beyond simple data theft or session hijacking, as it provides attackers with the capability to execute arbitrary code within the context of the victim administrator's browser session. This could enable complete compromise of the Firebox management interface, allowing unauthorized modification of security policies, access to sensitive network configuration data, or redirection of traffic through malicious proxies. The requirement for an authenticated administrator session limits the attack surface but does not eliminate the severity, as administrative credentials often possess extensive privileges within network security infrastructure. Organizations utilizing WatchGuard Fireware systems are particularly vulnerable if they maintain weak credential practices or if administrative accounts are compromised through phishing attacks, credential stuffing, or other authentication bypass techniques that align with ATT&CK technique T1110 for credential access.
Mitigation strategies for CVE-2025-6947 should prioritize immediate patch deployment for all affected Firebox versions, as WatchGuard has likely released security updates addressing this specific vulnerability. Network administrators should implement additional protective measures including regular security audits of administrative access, enforcement of strong authentication mechanisms such as multi-factor authentication, and monitoring for suspicious administrative activities. The implementation of web application firewalls and content security policies can provide additional layers of protection against exploitation attempts. Organizations should also consider segmenting administrative access through dedicated management networks and implementing strict access controls to minimize the potential impact of credential compromise. Regular vulnerability assessments and penetration testing should be conducted to identify similar weaknesses in other network security appliances and web applications within the organization's infrastructure.