OpenVPN before version 2.5.3 on Windows allows local users to load arbitrary dynamic loadable libraries via an OpenSSL configuration file i…

published 2021-07-02 5y ago modified 2026-06-17 4mo ago also EUVD-2021-26910

cvss: 7.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 28%
public exploits: 0; none known

OpenVPN before version 2.5.3 on Windows allows local users to load arbitrary dynamic loadable libraries via an OpenSSL configuration file if present, which allows the user to run arbitrary code with the same privilege level as the main OpenVPN process (openvpn.exe).

Patch / fix

fixed in 1

openvpn openvpn 2.5.3

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Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	4.4	AV:L/AC:M/Au:N/C:P/I:P/A:P

Affected products

n/a OpenVPN-GUI

Classification

Weakness

CWE-427 Uncontrolled Search Path Element

References

community.openvpn.net /openvpn/wiki/SecurityAnnouncements
vendor-advisory
community.openvpn.net /openvpn/wiki/CVE-2021-3606
vendor-advisory

Sources

CVE List CVE-2021-3606
NVD CVE-2021-3606

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