CVE WatchSep 9, 2026

CVE-2025-14733

WatchGuard Firebox Out of Bounds Write Vulnerability

CVSS

9.8

Critical

EPSS

26.5%

p98

KEV

YES

Dec 19, 2025

Exploit Today

0-100

Published: Dec 19, 2025 · Last modified: Sep 9, 2026 · CWE-787

EPSS · 30d

26.5%EPSS · 30 days26.5%

2026-09-172026-10-15

KEV catalog record

Product

WatchGuard / Firebox

Vulnerability

WatchGuard Firebox Out of Bounds Write Vulnerability

Added to KEV

Dec 19, 2025

Remediate by

Dec 26, 2025

Known ransomware use

Yes

Summary description

WatchGuard Fireware OS iked process contains an out of bounds write vulnerability in the OS iked process. This vulnerability may allow a remote unauthenticated attacker to execute arbitrary code and affects both the mobile user VPN with IKEv2 and the branch office VPN using IKEv2 when configured with a dynamic gateway peer.

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

Check for signs of potential compromise on all internet accessible instances after applying mitigations. For more information please see: https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2025-00027 ; https://nvd.nist.gov/vuln/detail/CVE-2025-14733

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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