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4.8Medium

Watchguard Fireware

CVE-2026-13375

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS (Autotask Technology Integration module) allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-13938. 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.

What this means for your business

  • It affects Watchguard Fireware. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, with an administrator login, but only after tricking someone into an action such as opening a file or a link.

What to do

  1. 1Check whether your company or your suppliers run Watchguard Fireware, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Check if you’re exposedBook a call

Scoring

CVSS
4.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
CVSS v4
4.8
Weakness
CWE-79
Assigned by
5d1c2695-1a31-4499-88ae-e847036fd7e3

Dates

Published
2026-07-03
Last modified
2026-08-28
Sources
NVD

Affected products

  • Watchguard Fireware12.4 - 12.12.1, 2025.1 - 2026.2.1, 12.5 - 12.5.18
  • Watchguard Firebox M270all versions
  • Watchguard Firebox M290all versions
  • Watchguard Firebox M370all versions
  • Watchguard Firebox M390all versions
  • Watchguard Firebox M440all versions
  • Watchguard Firebox M4600all versions
  • Watchguard Firebox M470all versions
  • Watchguard Firebox M4800all versions
  • Watchguard Firebox M5600all versions
  • Watchguard Firebox M570all versions
  • Watchguard Firebox M5800all versions

As listed in the NVD configuration data. Not a statement about your estate.

References