Heap-based Buffer Overflow Vulnerability in Fireware OS by WatchGuard
CVE-2026-81851

6.9MEDIUM

Key Information:

Vendor

Watchguard

Status
Fireware Os
Vendor
CVE Published:
27 August 2026

Badges

👾 Exploit Exists

What is CVE-2026-81851?

A vulnerability exists in Fireware OS's iked process that allows an authenticated administrator to exploit a heap-based buffer overflow. By saving a specially crafted configuration, the IKE daemon (iked) can be crashed, resulting in a denial of service. This presents significant risks for network performance and continuity, requiring immediate attention from system administrators to mitigate potential disruptions.

Affected Version(s)

Fireware OS Default 2025.0 < 2026.2.1

Fireware OS Default 12.0 < 12.12.1

Fireware OS EUCC 12.0 < 12.11.9

References

https://psirt.watchguard.com/CVE-2026-81851
vendor-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Cody Sixteen
.