Bug 1312082 (CVE-2016-2114)

Summary:	CVE-2016-2114 samba: Samba based active directory domain controller does not enforce smb signing
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	aavati, abokovoy, asn, gdeschner, jrivera, madam, nlevinki, rfortier, rhack, sbose, security-response-team, sgirijan, smohan, ssaha, vbellur
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	samba 4.4.1, samba 4.3.7, samba 4.2.10	Doc Type:	Bug Fix
Doc Text:	It was discovered that Samba did not enforce Server Message Block (SMB) signing for clients using the SMB1 protocol. A man-in-the-middle attacker could use this flaw to modify traffic between a client and a server.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2016-04-19 05:28:56 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Bug Depends On:	1322688, 1322689, 1322690, 1322691, 1322692, 1324807, 1325382, 1325383, 1325384, 1325385, 1325645, 1325649, 1325650, 1325651, 1326453
Bug Blocks:	1311915

Description Adam Mariš 2016-02-25 17:03:52 UTC

It was found that Samba based active directory domain controller does not enforce smb signing and opens possibility for man-in-the-middle attacks.

When Samba is configured as a Domain Controller, the default for the "server signing" should be "mandatory". During the early development of Samba 4 a new experimental file server located under source4/smb_server was used. But before the final 4.0.0 release upstream switched back to the file server under source3/smbd. But the logic for the correct default of "server signing" was not ported.

Currently all Samba versions >= 4.0.0 are affected.

Upstream bug:

https://bugzilla.samba.org/show_bug.cgi?id=11687

Comment 5 Huzaifa S. Sidhpurwala 2016-04-11 05:39:30 UTC

Acknowledgements:

Name: the Samba project
Upstream: Stefan Metzmacher (SerNet)

Comment 6 Huzaifa S. Sidhpurwala 2016-04-11 05:45:19 UTC

External Reference:

https://access.redhat.com/articles/2243351

Comment 7 Huzaifa S. Sidhpurwala 2016-04-12 17:11:57 UTC

Public via:

https://www.samba.org/samba/security/CVE-2016-2114.html

Comment 8 Siddharth Sharma 2016-04-12 17:28:43 UTC

Created samba tracking bugs for this issue:

Affects: fedora-all [bug 1326453]

Comment 9 errata-xmlrpc 2016-04-12 21:24:52 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 6.6 Extended Update Support
  Red Hat Enterprise Linux 6.5 Advanced Update Support
  Red Hat Enterprise Linux 6.4 Advanced Update Support
  Red Hat Enterprise Linux 6.2 Advanced Update Support

Via RHSA-2016:0620 https://rhn.redhat.com/errata/RHSA-2016-0620.html

Comment 10 errata-xmlrpc 2016-04-12 21:39:57 UTC

This issue has been addressed in the following products:

  Red Hat Gluster Storage 3.1 for RHEL 7
  Red Hat Gluster Storage 3.1 for RHEL 6

Via RHSA-2016:0614 https://rhn.redhat.com/errata/RHSA-2016-0614.html

Comment 11 errata-xmlrpc 2016-04-13 01:07:36 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7
  Red Hat Enterprise Linux 6

Via RHSA-2016:0612 https://rhn.redhat.com/errata/RHSA-2016-0612.html

Comment 12 errata-xmlrpc 2016-04-13 01:27:32 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7.1 Extended Update Support

Via RHSA-2016:0618 https://rhn.redhat.com/errata/RHSA-2016-0618.html

Comment 13 Fedora Update System 2016-04-13 20:21:41 UTC

samba-4.3.8-0.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 14 Fedora Update System 2016-04-14 04:21:25 UTC

samba-4.2.11-0.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.

Comment 15 Fedora Update System 2016-04-15 03:17:11 UTC

samba-4.4.2-1.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.