CVE-2021-3547

mediumpriority · track · 30EPSS 0.012 · 69 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.24% (69th) EPSS

CVSS 5.8 · medium

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.4

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–7.4

v2.05.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 4.9

v3.17.4highCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 2.2 · impact 5.2

v3.16.8mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimaryCWE-305US

affected products (3)

Products and version ranges known to be affected.

n/a OpenVPN 3 Core Library≤ 3.6 and 3.6.1enisa_euvdEU
openvpn openvpn= 3.6nvdUScpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
openvpn openvpn= 3.6.1nvdUScpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-07-12modified 2026-06-17

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+1889 more

references (8)

External citations — patches, advisories, analysis.

scry

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