CVE-2017-12166

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-10-04 · updated 2026-06-17
Weakness: CWE-787

Description

OpenVPN versions before 2.3.3 and 2.4.x before 2.4.4 are vulnerable to a buffer overflow vulnerability when key-method 1 is used, possibly resulting in code execution.

Affected products

Debian Linux: 9.0
OpenVPN: before 2.3.18; from 2.4.0 before 2.4.4 — fixed in 2.3.18, 2.4.4

How to fix

Upgrade to a fixed version: OpenVPN 2.3.18, 2.4.4. Check the vendor advisory for mitigations.

References

http://www.securityfocus.com/bid/101153
http://www.securitytracker.com/id/1039470
https://community.openvpn.net/openvpn/wiki/CVE-2017-12166
https://lists.debian.org/debian-lts-announce/2022/05/msg00002.html
http://www.securityfocus.com/bid/101153
http://www.securitytracker.com/id/1039470
https://community.openvpn.net/openvpn/wiki/CVE-2017-12166
https://lists.debian.org/debian-lts-announce/2022/05/msg00002.html

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