Which products and versions are affected by CVE-2025-9242?

Affected: Fireware (Watchguard) versions 2025.1; Fireware OS versions >= 12.0. The full list is in the CVE brief.

Is CVE-2025-9242 being exploited in the wild?

It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 21, 2025 and is known to be used in ransomware campaigns.

Is CVE-2025-9242 in the CISA KEV catalog?

Yes. It was added on Nov 12, 2025 with a federal remediation due date of Dec 3, 2025.

Is there a public exploit for CVE-2025-9242?

Public exploit code is available.

Is there a fix for CVE-2025-9242?

Fixed versions are available, including Fireware OS 12.11.4, Fireware OS 12.3.1+722811, Fireware OS 12.5.13.

How urgently should CVE-2025-9242 be patched?

Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Request A Demo

Vulnerability Intelligence

CVE-2025-9242

CriticalExploitedPublic exploit

An Out-of-bounds Write vulnerability in WatchGuard Fireware OS may allow a remote unauthenticated attacker to execute arbitrary code.

Published Sep 17, 2025 · Updated Aug 10, 2026

Key Facts

Patch immediately

CVE-2025-9242 is a critical-severity vulnerability (CVSS 9.3 v4) affecting Fireware (Watchguard), Fireware OS.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 21, 2025 and is known to be used in ransomware campaigns. Public exploit code is available.
EPSS estimates a 92% probability of exploitation in the next 30 days.
Fixed versions are available, including Fireware OS 12.11.4, Fireware OS 12.3.1+722811, Fireware OS 12.5.13.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v4

9.3

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

EPSS (30-day exploit likelihood)

92%

Higher than 99.8% of all scored CVEs

Exploited in the wild

Yes

4 catalog listings, used by ransomware

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2025-9242 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

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.

Known-Exploited Catalog Listings

Catalog	Added	Remediation due	Ransomware use
CISA KEV	Nov 12, 2025	Dec 3, 2025	Not reported
Industry KEV feed	Oct 21, 2025	Dec 3, 2025	Known
CIRCL KEV	Nov 12, 2025	Dec 3, 2025	Not reported
ENISA EUVD	Nov 12, 2025	n/a	Not reported

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.

Affected Products

3 affected entries in total

Product	Affected versions	Fixed in
FirewareWatchguard	2025.1	12.11.4
Fireware OS	>= 12.0	12.11.4

Patched Releases

Fireware OS

12.11.4, 12.3.1+722811, 12.5.13, 2025.1.1

Fireware

12.11.4, 12.5.13

Timeline

Publicly disclosed
Sep 17, 2025
Added to Industry KEV feed
Oct 21, 2025
Added to CISA KEV
Nov 12, 2025
Added to CIRCL KEV
Nov 12, 2025
Added to ENISA EUVD
Nov 12, 2025
Last updated
Aug 10, 2026

Weakness Type

CWE-787 Out-of-bounds Write

References

4 more references in the full CVE brief

FAQ

Common Questions.

An Out-of-bounds Write vulnerability in the WatchGuard Fireware OS iked process may allow a remote unauthenticated attacker to execute arbitrary code.
Affected: Fireware (Watchguard) versions 2025.1; Fireware OS versions >= 12.0. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 21, 2025 and is known to be used in ransomware campaigns.
Yes. It was added on Nov 12, 2025 with a federal remediation due date of Dec 3, 2025.
Public exploit code is available.
Fixed versions are available, including Fireware OS 12.11.4, Fireware OS 12.3.1+722811, Fireware OS 12.5.13.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Is CVE-2025-9242 Running On Your Attack Surface?

Brandefense maps vulnerabilities like this one to your internet-facing assets and tells you exactly where to patch.