CVE-2026-86133

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://psirt.watchguard.com/CVE-2026-86133	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:watchguard:fireware::::::::
	cpe:2.3:o:watchguard:fireware::::::::
	cpe:2.3:o:watchguard:fireware::::::::
	cpe:2.3:o:watchguard:fireware::::::::

History

06 Oct 2026, 20:28

Type	Values Removed	Values Added
First Time		Watchguard Watchguard fireware
References	~~() https://psirt.watchguard.com/CVE-2026-86133 -~~	() https://psirt.watchguard.com/CVE-2026-86133 - Patch, Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:o:watchguard:fireware::::::::

30 Sep 2026, 00:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-30 00:16

Updated : 2026-10-06 20:28

NVD link : CVE-2026-86133

Mitre link : CVE-2026-86133

CVE.ORG link : CVE-2026-86133

JSON object : View

Products Affected

watchguard

fireware

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

CWE-1284

Improper Validation of Specified Quantity in Input

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