Bug 1298033 (CVE-2016-0778)

Summary:	CVE-2016-0778 OpenSSH: Client buffer-overflow when using roaming connections
Product:	[Other] Security Response	Reporter:	Huzaifa S. Sidhpurwala <huzaifas>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	carnil, fedora, jaeshin, jjelen, jrusnack, mattias.ellert, riehecky, sardella, security-response-team, slawomir, tmraz, vg.aetera
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	openssh 7.1p2	Doc Type:	Bug Fix
Doc Text:	A buffer overflow flaw was found in the way the OpenSSH client roaming feature was implemented. A malicious server could potentially use this flaw to execute arbitrary code on a successfully authenticated OpenSSH client if that client used certain non-default configuration options.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-01-14 20:54:34 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:	1298217, 1298218, 1298630, 1298817, 1298818
Bug Blocks:	1298034

Description Huzaifa S. Sidhpurwala 2016-01-13 04:06:52 UTC

A buffer-overflow was found in the way OpenSSH client handled roaming connections. This buffer overflow, is present in the default configuration of the OpenSSH client but its exploitation requires two non-default options: a ProxyCommand, and either ForwardAgent (-A) or ForwardX11 (-X).

This buffer-overflow is not exploitable in the default configuration of OpenSSH package shipped with Red Hat Enterprise Linux.

Comment 2 Martin Prpič 2016-01-14 09:40:06 UTC

Acknowledgements:

Red Hat would like to thank Qualys for reporting this issue.

Comment 3 Martin Prpič 2016-01-14 15:20:48 UTC

Created openssh tracking bugs for this issue:

Affects: fedora-all [bug 1298630]

Comment 4 Martin Prpič 2016-01-14 15:22:03 UTC

Public now via upstream release 7.1p2:

http://www.openssh.com/txt/release-7.1p2

Comment 5 Martin Prpič 2016-01-14 17:33:41 UTC

A detailed analysis of this issue was published by Qualys at:

https://www.qualys.com/2016/01/14/cve-2016-0777-cve-2016-0778/openssh-cve-2016-0777-cve-2016-0778.txt

Comment 6 Tomas Hoger 2016-01-14 19:14:41 UTC

External References:

http://www.openssh.com/txt/release-7.1p2
https://www.qualys.com/2016/01/14/cve-2016-0777-cve-2016-0778/openssh-cve-2016-0777-cve-2016-0778.txt

Comment 7 errata-xmlrpc 2016-01-14 20:21:08 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2016:0043 https://rhn.redhat.com/errata/RHSA-2016-0043.html

Comment 8 Tomas Hoger 2016-01-15 07:43:29 UTC

Created gsi-openssh tracking bugs for this issue:

Affects: fedora-all [bug 1298817]
Affects: epel-7 [bug 1298818]

Comment 9 Fedora Update System 2016-01-29 00:21:50 UTC

gsi-openssh-7.1p2-1.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 10 Fedora Update System 2016-02-01 06:32:35 UTC

gsi-openssh-6.9p1-7.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.

Comment 11 Fedora Update System 2016-02-04 21:56:11 UTC

gsi-openssh-6.6.1p1-3.el7 has been pushed to the Fedora EPEL 7 stable repository. If problems still persist, please make note of it in this bug report.