Actively exploited in the wild
WatchGuard Firebox Out-of-Bounds Write Vulnerability
WatchGuard - Firebox · Listed in the CISA KEV since 2025-11-12. This indicates confirmed attacks in production environments.
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.
CVE-2025-9242
CriticalCVSS 9.8KEVExploitation Probability (EPSS)
Very high risk100th percentile - higher than 100% of all known CVEs
Summary
Out-of-bounds write vulnerability in the iked process of WatchGuard Fireware OS. A remote unauthenticated attacker can execute arbitrary code. Affects mobile user VPN with IKEv2 and branch office VPN using IKEv2 when configured with a dynamic gateway peer. If configurations were deleted but a branch office VPN to a static peer remains, the device may still be vulnerable.
Risk Assessment
An attacker can remotely execute code on the firewall, potentially leading to full compromise of the device and network.
Recommendation
Install security updates provided by WatchGuard for Fireware OS.
Original NVD description (English source)
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.