---
id: CVE-2026-86134
title: >-
  A NULL pointer dereference vulnerability in the WatchGuard Fireware OS
  authentication process allows a remote, unauthenticated attacker to crash the
  management daemon by sending a specially request to the login interface,
  resulting in a …
summary: >-
  A NULL pointer dereference vulnerability in the WatchGuard Fireware OS
  authentication process allows a remote, unauthenticated attacker to crash the
  management daemon by sending a specially request to the login interface,
  resulting in a …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
vendor: watchguard
product: fireware
affected:
  - 'fireware >= 12.0, < 12.5.21'
  - 'fireware >= 12.12, < 12.12.3'
  - 'fireware >= 2025.0, < 2026.2.3'
  - 'fireware >= 2026.3, < 2026.3.2'
patched:
  - fireware 2026.3.2
published: '2026-09-30'
updated: '2026-10-06'
sourceUpdated: '2026-10-06T17:30:29.910'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-86134'
references:
  - url: 'https://psirt.watchguard.com/CVE-2026-86134'
    label: 5d1c2695-1a31-4499-88ae-e847036fd7e3
tags:
  - nvd
  - cve.org
epss: 0.004
epssPercentile: 0.34087
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-30T14:38:22.384700Z'
scores:
  nvd: 7.5
  cna: 8.7
ingestedAt: '2026-09-30T03:56:19.556Z'
---

## Overview

A NULL pointer dereference vulnerability in the WatchGuard Fireware OS authentication process allows a remote, unauthenticated attacker to crash the management daemon by sending a specially request to the login interface, resulting in a denial of service.

## Affected

- `fireware >= 12.0, < 12.5.21`
- `fireware >= 12.12, < 12.12.3`
- `fireware >= 2025.0, < 2026.2.3`
- `fireware >= 2026.3, < 2026.3.2`

## Remediation

Upgrade past the affected range:

- `fireware 2026.3.2`