CVE-2025-9242
WatchGuard Firebox Out-of-Bounds Write Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 December 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
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.
- CVSS 4.0
- 9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 91.30% probability · 100th percentile
- CISA KEV
- Listed 12 November 2025 · due 3 December 2025
- Weakness
- CWE-787
- Affected
- watchguard/fireware
- Source
- 5d1c2695-1a31-4499-88ae-e847036fd7e3
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2025-00015 ; https://nvd.nist.gov/vuln/detail/CVE-2025-9242
References
- https://psirt.watchguard.com/CVE-2025-9242Broken Link
- https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2025-00015Vendor Advisory
- https://github.com/watchtowrlabs/watchTowr-vs-WatchGuard-CVE-2025-9242/blob/main/watchTowr-vs-WatchGuard-CVE-2025-9242.pyExploit
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-9242US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.