CVE-2021-3547

7.4 HIGH

OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an u...

Published: 2021-07-12 · Last updated: 2026-06-17

Severity and scoring

CVSS: 7.4 HIGH
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE: CWE-295, CWE-305

Affected products

Vendor	Product
openvpn	openvpn

Description

OpenVPN 3 Core Library version 3.6 and 3.6.1 allows a man-in-the-middle attacker to bypass the certificate authentication by issuing an unrelated server certificate using the same hostname found in the verify-x509-name option in a client configuration.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3547
[Patch]https://community.openvpn.net/openvpn/wiki/CVE-2021-3547
[Vendor advisory]https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements
[Patch]https://community.openvpn.net/openvpn/wiki/CVE-2021-3547
[Vendor advisory]https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements

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