CVE-2026-86133

Fireware OS Pre-Authentication Integer Underflow in iked Allows Remote Denial of Service

High 8.2 CVSS v4.0 › Published 2026-09-29Updated 2026-09-29

Summary #

An integer underflow vulnerability in the WatchGuard Fireware OS IKE daemon (iked) allows a remote attacker who has completed the initial IKEv2 handshake to crash the iked process by sending a specially crafted encrypted IKEv2 message, resulting in a denial of service.

Product status #

ProductAffectedNot affected
Fireware OS
Default >= 2026.3, < 2026.3.2, >= 2025.0, < 2026.2.3, >= 12.0, < 12.12.3>= 2026.3.2, >= 2026.2.3, >= 12.12.3
T15/T35 >= 12.0, < 12.5.21>= 12.5.21

Weakness Type and Impact #

  • CWECWE-191Integer Underflow (Wrap or Wraparound)
  • CWECWE-1284Improper Validation of Specified Quantity in Input
  • CAPECCAPEC-92Forced Integer Overflow
  • CAPECCAPEC-153Input Data Manipulation

Exploitation Status #

WatchGuard is not aware of any exploitation of this vulnerability in the wild.

Solution #

Fireware OS 2026.3.2, Fireware OS 2026.2.3, Fireware OS 12.12.3, Fireware OS 12.5.21

References #

    Credits #

    • WatchGuard AI Security Researchfinder