Out-of-Bounds Read Vulnerability in WatchGuard Fireware OS
CVE-2026-78009

8.7HIGH

Key Information:

Vendor

Watchguard

Status
Fireware Os
Vendor
CVE Published:
27 August 2026

Badges

👾 Exploit Exists

What is CVE-2026-78009?

An out-of-bounds read vulnerability in the WatchGuard Fireware OS iked process can be exploited by remote unauthenticated attackers. By sending specially crafted network traffic, these attackers may cause a Denial of Service (DoS) condition in the VPN processing, leading to potential disruption of service and impacting network availability.

Affected Version(s)

Fireware OS Default 2025.0 < 2026.2.2

Fireware OS Default 12.0 < 12.12.2

Fireware OS Default 2026.3 < 2026.3.1

References

https://psirt.watchguard.com/CVE-2026-78009
vendor-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
None
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

Discovered Internally by WatchGuard AI Security Research
.