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WatchGuard Firebox Zero-Day Exploited for Remote Code Execution

WatchGuardzero-dayremote code executionFireboxFireware OSexploitdevice hijackingsecurity updatesactive exploitationfirewallCVSSout-of-boundslogsvulnerabilityIKE_AUTH
Updated December 24, 2025 at 01:02 PM19 sources

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A critical zero-day vulnerability, identified as CVE-2025-14733, has been discovered in WatchGuard Firebox firewalls, allowing remote unauthenticated attackers to execute arbitrary code. The flaw, rated with a CVSS score of 9.3, resides in the iked process responsible for handling IKEv2 VPN connections, specifically affecting both Mobile User VPN and Branch Office VPN configurations. Attackers can exploit this out-of-bounds write vulnerability by sending specially crafted requests, potentially leading to full device compromise and firewall hijacking.

WatchGuard has confirmed active exploitation of this vulnerability in the wild, with threat actors targeting exposed devices. Indicators of compromise include suspicious IP addresses, unusually large certificate payloads in IKE_AUTH requests, long certificate chains, and unexpected crashes of the iked process. Administrators are urged to apply the latest security updates immediately and review their logs for signs of compromise. The vulnerability affects Fireware OS versions 11.10.2 through 11.12.4_Update1, 12.0 through 12.11.5, and 2025.1 through 2025.1.3.

Sources

December 23, 2025 at 12:00 AM
December 23, 2025 at 12:00 AM
December 22, 2025 at 12:00 AM
December 22, 2025 at 12:00 AM

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