This vulnerability (CVE-2026-13383) involves an out-of-bounds write (CWE-787) in the ikestubd process of WatchGuard Fireware OS. An authenticated user with elevated privileges can exploit this flaw by crafting specific requests to the Management Web UI, potentially leading to arbitrary code execution. The CVSS 4.0 score is 8.6, indicating high severity with network attack vector, low attack complexity, no user interaction, and high impact on confidentiality, integrity, and availability. Affected versions explicitly include 12.1, 12.5, and 2025.1. There is no vendor advisory or patch information available at this time.

Successful exploitation allows an authenticated privileged user to execute arbitrary code on the affected system, potentially compromising system integrity and availability. The vulnerability impacts confidentiality, integrity, and availability with high severity. There are no known exploits in the wild currently.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a patch is available, restrict access to the Management Web UI to trusted administrators only and monitor for suspicious activity. No official fix or temporary workaround has been published by WatchGuard.