CVE-2026-78011 - Vulnerability Details - OpenCVE

An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Vendors	Products
Watchguard	Fireware Os

No data.

No data.

References

Link	Providers
https://psirt.watchguard.com/CVE-2026-78011

History

Fri, 28 Aug 2026 19:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 27 Aug 2026 18:00:00 +0000

Type	Values Removed	Values Added
Description		An integer underflow vulnerability in the WatchGuard Fireware OS iked process allows a remote unauthenticated attacker to create a Denial of Service (DoS) condition in VPN processing by sending specially crafted network traffic.
Title		Fireware OS Integer Underflow in Iked Allows Unauthenticated Denial of Service (DoS)
First Time appeared		Watchguard Watchguard fireware Os
Weaknesses		CWE-191 CWE-787
CPEs		cpe:2.3:a:watchguard:fireware_os::::::::
Vendors & Products		Watchguard Watchguard fireware Os
References		https://psirt.watchguard.com/CVE-2026-78011
Metrics		cvssV4_0 `{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}`

MITRE

Status: PUBLISHED

Assigner: WatchGuard

Published: 2026-08-27T23:24:33.126Z

Updated: 2026-09-03T20:49:55.699Z

Reserved: 2026-08-21T21:46:48.681Z

Link: CVE-2026-78011

Vulnrichment

Updated: 2026-08-28T16:51:37.687Z

NVD

Status : Deferred

Published: 2026-08-28T02:16:22.563

Modified: 2026-09-03T21:17:22.293

Link: CVE-2026-78011

Redhat

No data.

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