CVE-2016-6329

medium

Description

OpenVPN, when using a 64-bit block cipher, makes it easier for remote attackers to obtain cleartext data via a birthday attack against a long-duration encrypted session, as demonstrated by an HTTP-over-OpenVPN session using Blowfish in CBC mode, aka a "Sweet32" attack.

References

https://sweet32.info/

https://security.gentoo.org/glsa/201611-02

https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05369403

http://www.securitytracker.com/id/1036695

http://www.securityfocus.com/bid/92631

http://www-01.ibm.com/support/docview.wss?uid=swg21995039

http://www-01.ibm.com/support/docview.wss?uid=swg21991482

http://www-01.ibm.com/support/docview.wss?uid=nas8N1021697

https://thehackernews.com/2026/07/study-of-281-free-android-vpn-apps.html

https://medium.com/tenable-techblog/meltdown-of-critical-ics-vulnerabilities-8af3a1a13e6a

https://euvd.enisa.europa.eu/vulnerability/EUVD-2016-7256

https://community.openvpn.net/openvpn/wiki/SWEET32

https://cert-portal.siemens.com/productcert/pdf/ssa-556833.pdf

Details

Source: Mitre, NVD

Published: 2017-01-31

Updated: 2026-06-17

Risk Information

CVSS v2

Base Score: 4.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: Medium

EPSS

EPSS: 0.0594