# WatchGuard Fireware OS RCE via IKEv2 gateway flaw

Published: 2026-06-09 · Severity: high · Sectors: government-national, financial-services, technology, infrastructure
Canonical: https://vorant.io/reports/66e533bc-dd17-5103-8854-86a3ff885ac2/watchguard-fireware-os-rce-via-ikev2-gateway-flaw

> Out-of-bounds write in WatchGuard Fireware OS iked process allows unauthenticated RCE; no active exploitation reported.

WatchGuard has disclosed CVE-2025-9242, an out-of-bounds write vulnerability in the iked process of Fireware OS that runs on Firebox firewalls. The flaw affects the mobile user VPN with IKEv2 and branch office VPN with IKEv2 when configured to dynamic gateway peers. A remote unauthenticated attacker can exploit this to execute arbitrary code with the privileges of the affected user account.

The vulnerability impacts Fireware OS versions 11.10.2 through 11.12.4_Update1, 12.0 through 12.11.3, and 2025.1. CIS reports no current in-the-wild exploitation. The risk to administrators is severe given the unauthenticated nature and code execution capability; standard users would have lower impact due to reduced privileges. Notably, a Firebox that previously had IKEv2 mobile or dynamic gateway configs but deleted them may remain vulnerable if a static gateway peer VPN is still configured.

Defenders should apply WatchGuard patches immediately after testing. Segmentation, least-privilege account management, and vulnerability scanning are recommended mitigations pending patch deployment.

## Mentioned in this report

- Vulnerabilities: CVE-2025-9242 (KEV)

## Detection guidance (public sample)

### IKE Daemon (iked) Spawning a Shell or Command Interpreter

ATT&CK: T1190

Detects the iked IKE daemon spawning a shell or scripting or download utility, which is consistent with post-exploitation code execution after an iked memory-corruption flaw such as CVE-2025-9242. Auto-generated starting point — validate and tune in your environment before deploying. IOC matches can false-positive on shared infrastructure and decay as adversary infrastructure rotates.

```yaml
title: IKE Daemon (iked) Spawning a Shell or Command Interpreter
description: Detects the iked IKE/IPsec daemon spawning a shell, scripting interpreter
  or download utility. iked normally does not launch interpreters, so this parent/child
  relation is consistent with code execution after exploitation of an iked out-of-bounds
  write such as CVE-2025-9242 on WatchGuard Fireware OS. Only applies where process
  telemetry exists for Linux-based appliances or hosts running iked.
tags:
- attack.initial-access
- attack.t1190
logsource:
  category: process_creation
  product: linux
detection:
  selection_parent:
    ParentImage|endswith: /iked
  selection_child:
    Image|endswith:
    - /sh
    - /bash
    - /dash
    - /ash
    - /busybox
    - /python
    - /python3
    - /perl
    - /nc
    - /ncat
    - /wget
    - /curl
    - /tftp
  condition: selection_parent and selection_child
falsepositives:
- Vendor diagnostic or restart scripts that the IKE daemon invokes through a shell
  on some appliance builds
- Other IKE daemons that are also named iked and call helper scripts for tunnel up/down
  hooks
level: high
id: 30492b05-4135-5d33-bceb-d1c8f9088432
status: experimental
author: Vorant
references:
- https://www.cisecurity.org/advisory/a-vulnerability-in-watchguard-fireware-os-could-allow-for-arbitrary-code-execution_2025-087
```

Behavioural rules are generated from public reporting — validate in your environment before deploying.

Source reporting: https://www.cisecurity.org/advisory/a-vulnerability-in-watchguard-fireware-os-could-allow-for-arbitrary-code-execution_2025-087

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