CVE-2021-3547

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.

Categories

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.05%
Vendor Advisory openvpn.net Vendor Advisory openvpn.net
Affected: n/a OpenVPN 3 Core Library
Published at:
Updated at:

References

Link Tags
https://community.openvpn.net/openvpn/wiki/SecurityAnnouncements vendor advisory
https://community.openvpn.net/openvpn/wiki/CVE-2021-3547 patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-3547?
CVE-2021-3547 has been scored as a high severity vulnerability.
How to fix CVE-2021-3547?
To fix CVE-2021-3547, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3547 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3547 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3547?
CVE-2021-3547 affects n/a OpenVPN 3 Core Library.
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