CVE-2026-11771CWE-121CWE-193CWE-787

CVE-2026-11771

High · published July 30, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
30.2
In the wild
Unconfirmed
What it is

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

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00375 · 30.2th percentile
Weaknesses
CWE-121 · Stack-based Buffer Overflow; CWE-193 · Off-by-one Error; CWE-787 · Out-of-bounds Write
Published
2026-07-30T21:16Z
Affected products (2)
ProductVersionsFixed in
openvpn/openvpn≥ 2.1.0, < 2.6.212.6.21
openvpn/openvpn≥ 2.7, < 2.7.52.7.5
References (3)
https://community.openvpn.net/ReleaseHistory#openvpn-2621-released-1-july-2026 · [email protected]https://community.openvpn.net/ReleaseHistory#openvpn-275-released-1-july-2026 · [email protected]https://community.openvpn.net/Security%20Announcements/CVE-2026-11771 · [email protected]
EPSS history
Timeline
  • 30 JUL 16:36Z
    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…
    cvelistv5