CVE-2026-13377
published 2026-07-03CVE-2026-13377: Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS SIP Proxy module allows…
PriorityP423medium4.8CVSS 3.1
AVNACLPRHUIRSCCLILAN
EPSS
0.27%
19.5th percentile
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.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| watchguard | fireware | >= 12.0 < 12.12.1 | 12.12.1 |
| watchguard | fireware | 12.5 – 12.5.18 | — |
| watchguard | fireware | >= 2025.1 < 2026.2.1 | 2026.2.1 |
CVSS provenance
nvdv3.14.8MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
nvdv4.04.8MEDIUMCVSS: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:X/V:X/RE:X/U:X
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VulDB
WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 cross site scripting (wgsa-2026-00019 / WID-SEC-2026-2193)
vuldb·2026-08-30·CVSS 4.8
CVE-2026-13377 [MEDIUM] WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 cross site scripting (wgsa-2026-00019 / WID-SEC-2026-2193)
A vulnerability has been found in WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 and classified as problematic. This affects an unknown function. The manipulation leads to cross site scripting.
This vulnerability is listed as CVE-2026-13377. The attack may be initiated remotely. There is no available exploit.
GHSA
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS SIP Proxy module allows Stored XSS.
ghsa_unreviewed·2026-07-03·CVSS 4.8
CVE-2026-13377 [MEDIUM] CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS SIP Proxy module allows Stored XSS.
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.
This issue affects Fireware OS 12.0 up to and including 12.12, 12.5 up to and including 12.5.18, and 2025.1 up to and including 2026.2.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-03
Published