CVE WatchAug 10, 2026

CVE-2025-9242

WatchGuard Firebox Out-of-Bounds Write Vulnerability

CVSS

9.8

Critical

EPSS

91.3%

p100

KEV

YES

Nov 12, 2025

Exploit Today

0-100

Published: Sep 17, 2025 · Last modified: Aug 10, 2026 · CWE-787

EPSS · 30d

91.1%EPSS · 30 days91.3%

2026-08-022026-08-30

KEV catalog record

Product

WatchGuard / Firebox

Vulnerability

WatchGuard Firebox Out-of-Bounds Write Vulnerability

Added to KEV

Nov 12, 2025

Remediate by

Dec 3, 2025

Known ransomware use

Summary description

WatchGuard Firebox contains an out-of-bounds write vulnerability in the OS iked process that may allow a remote unauthenticated attacker to execute arbitrary code.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Notes

https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2025-00015 ; https://nvd.nist.gov/vuln/detail/CVE-2025-9242

Technical description

An Out-of-bounds Write vulnerability in the WatchGuard Fireware OS iked process may allow a remote unauthenticated attacker to execute arbitrary code. This vulnerability affects both the mobile user VPN with IKEv2 and the branch office VPN using IKEv2 when configured with a dynamic gateway peer. If the Firebox was previously configured with the mobile user VPN with IKEv2 or a branch office VPN using IKEv2 to a dynamic gateway peer, and both of those configurations have since been deleted, that Firebox may still be vulnerable if a branch office VPN to a static gateway peer is still configured.

Official references

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