Bug 1369386 (CVE-2016-6329)

Summary:	CVE-2016-6329 openvpn: Birthday attack against BF-CBC used by default (SWEET32)
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	security-response-team, slawomir
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 02:57:46 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1369833, 1369834
Bug Blocks:

Description Adam Mariš 2016-08-23 09:24:16 UTC

Ciphers with 64-bit block sizes used in CBC mode were found to be vulnerable to birthday attack when key renegotiation doesn't happen frequently or at all in long running connections. Blowfish cipher as used in OpenVPN by default is vulnerable to this attack, that allows remote attacker to recover partial plaintext information (XOR of two plaintext blocks).

External References:

https://community.openvpn.net/openvpn/wiki/SWEET32
https://sweet32.info/

Comment 1 Adam Mariš 2016-08-23 09:24:20 UTC

Acknowledgments:

Name: OpenVPN
Upstream: Karthikeyan Bhargavan (Inria), Gaëtan Leurent (Inria)

Comment 2 Adam Mariš 2016-08-24 14:06:31 UTC

Created openvpn tracking bugs for this issue:

Affects: fedora-all [bug 1369833]
Affects: epel-all [bug 1369834]

Comment 3 Product Security DevOps Team 2019-06-08 02:57:46 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.