CVE-2013-2061

Severity: low (CVSS 2.6 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2013-11-18 · updated 2026-06-16
Weakness: CWE-200

Description

The openvpn_decrypt function in crypto.c in OpenVPN 2.3.0 and earlier, when running in UDP mode, allows remote attackers to obtain sensitive information via a timing attack involving an HMAC comparison function that does not run in constant time and a padding oracle attack on the CBC mode cipher.

Affected products

Opensuse: 11.4
OpenVPN: through 2.3.0; 1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.3.2, 1.4.0 (+7)
OpenVPN Access Server: 2.0.0

References

http://lists.fedoraproject.org/pipermail/package-announce/2013-May/105568.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/105609.html
http://lists.opensuse.org/opensuse-updates/2013-11/msg00012.html
http://lists.opensuse.org/opensuse-updates/2013-11/msg00016.html
http://www.mandriva.com/security/advisories?name=MDVSA-2013:167
http://www.openwall.com/lists/oss-security/2013/05/06/6
https://bugs.gentoo.org/show_bug.cgi?id=468756
https://bugzilla.redhat.com/show_bug.cgi?id=960192
https://community.openvpn.net/openvpn/wiki/SecurityAnnouncement-f375aa67cc
https://github.com/OpenVPN/openvpn/commit/11d21349a4e7e38a025849479b36ace7c2eec2ee
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/105568.html
http://lists.fedoraproject.org/pipermail/package-announce/2013-May/105609.html

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