CVE-2026-40215

OpenVPN TLS Session Promotion Race Condition Causing Crash or Memory Leak

Published Jun 8, 2026 CVSS 4.0 · 6.1 Medium EPSS < 1% KEV · Not listed
Description
A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4653-1 openvpn security update
Debian DLA Debian DLA DLA-4653-2 openvpn regression update
Debian DSA Debian DSA DSA-6289-1 openvpn security update
Ubuntu USN Ubuntu USN USN-8286-1 OpenVPN vulnerabilities
History
Type Values Removed Values Added
CPEs cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H'}

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title OpenVPN TLS Session Promotion Race Condition Causing Crash or Memory Leak
Type Values Removed Values Added
First Time appeared Openvpn
Openvpn openvpn
Vendors & Products Openvpn
Openvpn openvpn
Type Values Removed Values Added
Description A race condition in OpenVPN 2.6.0 through 2.6.19 and 2.7_alpha1 through 2.7.1 allows remote attackers to potentially cause a server crash or leak heap memory via a use-after-free triggered during TLS session promotion.
Weaknesses CWE-125
CWE-416
References
Metrics cvssV4_0

{'score': 6.1, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:N/VA:H/SC:L/SI:N/SA:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
OpenVPN
Published
Updated
Jun 16, 2026, 12:24 PM
Reserved
Apr 13, 2026, 10:28 AM
Status
Analyzed
Published
Jun 8, 2026, 9:16 PM
Modified
Aug 11, 2026, 1:06 PM