All vulnerabilities
CVE-2026-93862

Fireware OS Out-of-Bounds Read in FireCluster Sync Allows Denial of Service

WatchGuard Fireware OSNetwork & edge
Open in ThreatlineRecord JSON
CVSS
7.2High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed in2026.4Also 12.12.4, 12.5.22CVE List
Published27 Oct 2026Updated 27 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

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.

Text from CVE List

Affected versions 3

  • Fireware OSaffected: 2025.1 before 2026.4CVE List
  • Fireware OSaffected: 12.0 before 12.12.4CVE List
  • Fireware OSaffected: 12.0 before 12.5.22CVE List

References 1