CVE-2026-13122

Publication date 3 July 2026

Last updated 8 July 2026

Ubuntu priority

Description

OpenVPN version 2.6.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows remote attackers to cause a denial of service via a malformed authentication token that triggers a reachable assertion when external-auth is enabled

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
openvpn	26.04 LTS resolute	Needs evaluation
	25.10 questing	Needs evaluation
	24.04 LTS noble	Needs evaluation
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

mdeslaur

versions earlier than 2.6.0 don't appear to be vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
openvpn	Upstream: 010b6c8

Severity score breakdown

CVSS version: CVSS v4.0

Base score 5.9 · Medium

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Attack requirements	Present
Privileges required	Low
User interaction	Passive
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

Scores

Parameter	Value
Base score	5.9 · Medium
Base + Threat score	-
Base + Environmental score	-
Base + Threat + Environmental score	-

Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N