---
id: CVE-2026-93862
title: Fireware OS Out-of-Bounds Read in FireCluster Sync Allows Denial of Service
summary: >-
  An out-of-bounds read vulnerability in the FireCluster Sync processing allows
  an attacker positioned on the cluster interconnect, such as a compromised
  cluster peer or an on-path network attacker, to repeatedly crash the
  firewall's clust…
severity: high
cvss: 7.2
cvssVector: 'CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-125
  - CWE-129
  - CWE-787
  - CWE-823
vendor: WatchGuard
product: Fireware OS
affected:
  - fireware_os >= 2025.1 < 2026.4
  - fireware_os >= 12.0 < 12.12.4
  - fireware_os >= 12.0 < 12.5.22
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T15:52:28.633Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-93862'
references:
  - url: 'https://psirt.watchguard.com/CVE-2026-93862'
tags:
  - cve.org
ingestedAt: '2026-10-27T16:11:59.480Z'
---

## Overview

An out-of-bounds read vulnerability in the FireCluster Sync processing allows an attacker positioned on the cluster interconnect, such as a compromised cluster peer or an on-path network attacker, to repeatedly crash the firewall's cluster synchronization process by sending specially crafted network traffic, resulting in a sustained denial of service.

## Affected

- `fireware_os >= 2025.1 < 2026.4`
- `fireware_os >= 12.0 < 12.12.4`
- `fireware_os >= 12.0 < 12.5.22`

## Remediation

Fireware OS 2026.4, Fireware OS 12.12.4, Fireware OS 12.5.22