CVE-2026-11771
High
Description
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
SeverityHigh
CVSS7.5
Exploit probability—
ProductOpenvpn
PublishedJul 30, 2026
First seenJul 30, 2026
How to fix
Update
- openvpn openvpn2.6.21, 2.7.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| openvpn openvpn | 2.1.0 ≤ v < 2.6.21, 2.7 ≤ v < 2.7.5 | 2.6.21, 2.7.5 |
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