CVE-2026-13376
published 2026-07-03CVE-2026-13376: Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS spamBlocker module allows…
PriorityP424medium4.8CVSS 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 spamBlocker module allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-1071.
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.
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-2026-00018 / WID-SEC-2026-2193)
vuldb·2026-08-30·CVSS 4.8
CVE-2026-13376 [MEDIUM] WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 cross site scripting (wgsa-2026-00018 / WID-SEC-2026-2193)
A vulnerability, which was classified as problematic, was found in WatchGuard Fireware OS up to 12.5.18/12.12/2026.2. The impacted element is an unknown function. Executing a manipulation can lead to cross site scripting.
This vulnerability is tracked as CVE-2026-13376. The attack can be launched remotely. No exploit exists.
GHSA
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS spamBlocker module allows Stored XSS.
ghsa_unreviewed·2026-07-03·CVSS 4.8
CVE-2026-13376 [MEDIUM] CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS spamBlocker module allows Stored XSS.
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS spamBlocker module allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-1071.
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