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Vulnerability record · CVE-2026-13377 · published 3 July 2026

CVE-2026-13377: Watchguard fireware cross-site scripting vulnerability

Watchguard · Fireware

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.

4.8 CVSS 4.0 Medium EPSS 0.27% · top 82.7% CWE-79 · Cross-site scripting
4.8CVSS 4.0 base score
0.27%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
28 Aug 2026Last modified by NVD

Description

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://psirt.watchguard.com/CVE-2026-13377
https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2026-00019 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2026-13377), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.