CISA Flags Critical WatchGuard Fireware Flaw Exposing 54,000 Fireboxes to No-Login Attacks
Nov 13, 2025
Vulnerability / Network Security
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Wednesday added a critical security flaw impacting WatchGuard Fireware to its Known Exploited Vulnerabilities ( KEV ) catalog, based on evidence of active exploitation. The vulnerability in question is CVE-2025-9242 (CVSS score: 9.3), an out-of-bounds write vulnerability affecting Fireware OS 11.10.2 up to and including 11.12.4_Update1, 12.0 up to and including 12.11.3 and 2025.1. "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," CISA said in an advisory. Details of the vulnerability were shared by watchTowr Labs last month, with the cybersecurity company stating that the issue stems from a missing length check on an identification buffer used during the IKE handshake process. "The server does attempt certificate validation, but that validation happens after the vulnerable code run...
