CVE.RADIO
FREN

CVE-2026-11771

OpenVPNVulnerabilityCVSS 7.0

OpenVPN version 2.1.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows attackers via an off-by-one buffer write in the NTLM proxy authentication to potentially cause a crash via a crafted NTLM response from a malicious proxy server

No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.

Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.

CVE-2026-11771 OpenVPN Vulnerability

Severity metrics

CVSS 4.0 : 7.0 HIGH

Attack vectorNetwork (remote)
Attack complexityHigh
Attack requirementsPresent
Privileges requiredNone
User interactionPassive
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Subsequent confidentialityNone
Subsequent integrityNone
Subsequent availabilityHigh

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

Affected & fixed versions by distribution

Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.

No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.

Sources

Advisory NVD CVE.org

Other vulnerabilities in OpenVPN

Published 2026-07-30 · source: NVD