WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 cross site scripting

Summaryinfo

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-2026-13376. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in WatchGuard Fireware OS up to 12.5.18/12.12/2026.2 and classified as problematic. This issue affects an unknown part. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

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.

It is possible to read the advisory at watchguard.com. The identification of this vulnerability is CVE-2026-13376 since 06/25/2026. The exploitation is known to be easy. The attack may be initiated remotely. Additional levels of successful authentication are necessary for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• WatchGuard

Name

• Fireware OS

Version

• 12.0
• 12.1
• 12.2
• 12.3
• 12.4
• 12.5
• 12.5.0
• 12.5.1
• 12.5.2
• 12.5.3
• 12.5.4
• 12.5.5
• 12.5.6
• 12.5.7
• 12.5.8
• 12.5.9
• 12.5.10
• 12.5.11
• 12.5.12
• 12.5.13
• 12.5.14
• 12.5.15
• 12.5.16
• 12.5.17
• 12.5.18
• 12.6
• 12.7
• 12.8
• 12.9
• 12.10
• 12.11
• 12.12
• 2026.0
• 2026.1
• 2026.2

License

• commercial

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Entryinfo

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