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

Summaryinfo

A vulnerability, which was classified as problematic, has been found in WatchGuard Fireware OS up to 12.5.18/12.12/2026.2. The affected element is an unknown function. Performing a manipulation results in cross site scripting. This vulnerability is identified as CVE-2026-13374. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, was found in WatchGuard Fireware OS up to 12.5.18/12.12/2026.2. This affects an unknown functionality. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as 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. This is going to have an impact on integrity. The summary by CVE is:

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS (ConnectWise Technology Integration module) allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-13937. This issue affects Fireware OS 12.4 up to and including 12.12, 12.5 up to and including 12.5.18, and 2025.1 up to and including 2026.2.

The advisory is shared at watchguard.com. This vulnerability is uniquely identified as CVE-2026-13374 since 06/25/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. The exploitation needs additional levels of successful authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

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

Several companies clearly confirm that VulDB is the primary source for best 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

• 🔒
• 🔒
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CPE 2.2info

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• 🔒
• 🔒

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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