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CVE-2026-13373 WatchGuard CVE debrief

CVE-2026-13373 is a Stored Cross-Site Scripting (XSS) vulnerability in the WatchGuard Fireware OS, specifically in the Tigerpaw Technology Integration module. This vulnerability is an additional unmitigated attack path for CVE-2025-13936. Affected versions include 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.

Vendor
WatchGuard
Product
Fireware OS
CVSS
MEDIUM 4.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-03
Original CVE updated
2026-08-28
Advisory published
2026-07-03
Advisory updated
2026-08-28

Who should care

This vulnerability affects users of WatchGuard Fireware OS versions 12.4 through 12.12, 12.5 through 12.5.18, and 2025.1 through 2026.2. System administrators and security teams responsible for managing and securing WatchGuard Firebox devices should prioritize patching this vulnerability to prevent potential XSS attacks.

Technical summary

The CVE-2026-13373 vulnerability is caused by improper neutralization of input during web page generation, leading to a Stored XSS vulnerability. This issue allows an attacker to inject malicious scripts into the application, which can then be executed by other users. The vulnerability has a CVSS score of 4.8 and a medium severity level. The CVSS vector is 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:X/V:X/RE:X/U:X.

Defensive priority

Medium priority should be given to patching this vulnerability, as it is a Stored XSS vulnerability with a medium CVSS score. However, given that this is an additional unmitigated attack path for CVE-2025-13936, it is essential to address this vulnerability promptly to prevent potential attacks.

Recommended defensive actions

  • Apply the patches provided by WatchGuard for the affected Fireware OS versions.
  • Upgrade to a non-vulnerable version of Fireware OS.
  • Implement additional security controls, such as input validation and output encoding, to prevent XSS attacks.
  • Monitor the affected systems for any suspicious activity.
  • Review and update incident response plans to address potential XSS attacks.

Evidence notes

The CVE-2026-13373 vulnerability was published on July 3, 2026, and last modified on July 9, 2026. The NVD entry is currently Analyzed. The vulnerability is related to CWE-79, Improper Neutralization of Input During Web Page Generation.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-13373 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-13373

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-13373 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-13373

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2026-00015

    5d1c2695-1a31-4499-88ae-e847036fd7e3 - Vendor Advisory

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.