CVE-2026-13377mediumCWE-79

CVE-2026-13377: medium-severity vulnerability in WatchGuard Fireware OS

WatchGuard Firebox Stored Cross-Site-Scripting (XSS) Vulnerability in SIP Proxy Configuration

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 4.8epss 0.3%
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS SIP Proxy module allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-6947.
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Affected products
WatchGuard · Fireware OS
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