Security tracker
CVE-2025-9242: WatchGuard Firebox Out-of-Bounds Write Vulnerability
In short
WatchGuard Firebox has a weakness classified as out-of-bounds write (CWE-787). CISA added it to its Known Exploited Vulnerabilities catalog on 2025-11-12. NVD lists CVSS 4.0 at 9.3 CRITICAL.
What it is
“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 KEV, retrieved 2026-11-01
“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.” — NVD, retrieved 2026-11-01
Who is affected
WatchGuard Firebox. NVD lists the following versions as affected:
- Versions from 11.10.2 inclusive, before 12.11.4
- Versions from 11.10.2 inclusive, before 12.5.13
- Versions version 2025.1
Exploitation status
CISA KEV added: 2025-11-12. Known ransomware campaign use: Not reported by CISA. Due date CISA set for US federal civilian agencies: 2025-12-03.
Scores
NVD CVSS 4.0: 9.3 CRITICAL; vector CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source 5d1c2695-1a31-4499-88ae-e847036fd7e3.
EPSS by FIRST: 92.22%; percentile 99.82; score date 2026-10-31. EPSS estimates the probability of exploitation in the next 30 days.
CWE: CWE-787.
Timeline
| Date | Event |
|---|---|
| 2025-09-17T08:15:33.960 | NVD published |
| 2025-11-12 | CISA KEV added |
| 2025-12-03 | CISA KEV due |
| 2026-08-10T19:59:12.133 | NVD last modified |
| 2026-10-31 | FIRST EPSS score |
CISA 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.” — CISA KEV
What to do
- Confirm whether you run WatchGuard Firebox and which version.
- Apply the vendor update or mitigation in the advisory.
- Follow CISA’s required action.
- Review the vendor guidance on signs of compromise.
- Track the fix through completion.
Sources and dates
CISA Known Exploited Vulnerabilities Catalog, version 2026.10.30; retrieved 2026-11-01. CISA KEV data: CC0 1.0. No endorsement by CISA.
NVD retrieved: 2026-11-01. This product uses the NVD API but is not endorsed or certified by the NVD.
EPSS scores by FIRST; score date 2026-10-31.
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