WatchGuard Fireware OS CVE-2026-78899 Unauth DoS via iked OOB Read

WatchGuard Firewall Vulnerability CVE-2026-78899 Key Information Summary Vulnerability Overview CVE ID: CVE-2026-78899 Title: Unauthenticated Denial of Service (DoS) Caused by Out-of-Bounds Read in Fireware OS Severity: High (CVSS v4.0 Score 8.7) Publish/Update Date: 2026-08-27 Vulnerability Description: The iked process in WatchGuard Firewall OS has an out-of-bounds read vulnerability. A remote unauthenticated attacker can send specially crafted network traffic to trigger an out-of-bounds read during VPN processing, resulting in a heap allocation of approximately 196 KiB, causing the iked process to crash and leading to a denial of service for the VPN service. Impact: An unauthenticated attacker who has completed the IKEv2 SA_INIT exchange can send a specially crafted encrypted INFORMATIONAL message containing a malformed DELETE payload, triggering an out-of-bounds read that crashes the iked process, rendering the VPN service unavailable. Under specific heap layouts, this vulnerability may also leak adjacent heap memory (such as key material or certificate data from other IKE SAs) to the attacker. Affected Scope (Impacted Versions) Weakness Types CWE-20: Improper Input Validation CWE-125: Out-of-Bounds Read CAPEC-540: Buffer Overflow Exploitation Status WatchGuard is currently not aware that this vulnerability is being exploited in the wild. Remediation Upgrade to the following versions: Fireware OS 2026.2.2 Fireware OS 12.12.2 Fireware OS 12.5.20 Other Discoverer: Discovered internally by the WatchGuard AI Security Research Team (marked as "finder") Reference: The formal record can be viewed at cve.org > Note: This page does not include POC code or exploit code blocks.

Goal Reached Thanks to every supporter — we hit 100%!

WatchGuard Fireware OS CVE-2026-78899 Unauth DoS via iked OOB Read