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Red Hat Enterprise Linux 7 RHSA-2016:1486 Moderate: Samba Security Fix

red hat
Calendar Grey July 26, 2016
Scroller Redhat
This release focuses on enhancing security measures and rectifying issues within Samba for Red Hat Enterprise Linux 7, presenting a moderate level of security concern.
An update for samba is now available for Red Hat Enterprise Linux 7

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, the smb service will be restarted automatically.

Summary

Samba is an open-source implementation of the Server Message Block (SMB) protocol and the related Common Internet File System (CIFS) protocol, which allow PC-compatible machines to share files, printers, and various information.
Security Fix(es):
* A flaw was found in the way Samba initiated signed DCE/RPC connections. A man-in-the-middle attacker could use this flaw to downgrade the connection to not use signing and therefore impersonate the server. (CVE-2016-2119)
Red Hat would like to thank the Samba project for reporting this issue. Upstream acknowledges Stefan Metzmacher as the original reporter.
Bug Fix(es):
* Previously, the "net" command in some cases failed to join the client to Active Directory (AD) because the permissions setting prevented modification of the supported Kerberos encryption type LDAP attribute. With this update, Samba has been fixed to allow joining an AD domain as a user. In addition, Samba now uses the machine account credentials to set up the Kerberos encryption types within AD for the joined machine. As a result, using "net" to join a domain now works more reliably. (BZ#1351260)
* Previously, the idmap_hash module worked incorrectly when it was used together with other modules. As a consequence, user and group IDs were not mapped properly. A patch has been applied to skip already configured modules. Now, the hash module can be used as the default idmap configuration back end and IDs are resolved correctly. (BZ#1350759)

Topics%20covered

Topics Covered

security advisory moderate red hat samba security fix attack DCE/RPC

References

https://access.redhat.com/security/cve/CVE-2016-2119 https://access.redhat.com/security/updates/classification#moderate

Package List

Red Hat Enterprise Linux Client (v. 7):
Source: samba-4.2.10-7.el7_2.src.rpm
noarch: samba-common-4.2.10-7.el7_2.noarch.rpm
x86_64: libsmbclient-4.2.10-7.el7_2.i686.rpm libsmbclient-4.2.10-7.el7_2.x86_64.rpm libwbclient-4.2.10-7.el7_2.i686.rpm libwbclient-4.2.10-7.el7_2.x86_64.rpm samba-client-4.2.10-7.el7_2.x86_64.rpm samba-client-libs-4.2.10-7.el7_2.i686.rpm samba-client-libs-4.2.10-7.el7_2.x86_64.rpm samba-common-libs-4.2.10-7.el7_2.x86_64.rpm samba-common-tools-4.2.10-7.el7_2.x86_64.rpm samba-debuginfo-4.2.10-7.el7_2.i686.rpm samba-debuginfo-4.2.10-7.el7_2.x86_64.rpm samba-libs-4.2.10-7.el7_2.i686.rpm samba-libs-4.2.10-7.el7_2.x86_64.rpm samba-winbind-4.2.10-7.el7_2.x86_64.rpm samba-winbind-clients-4.2.10-7.el7_2.x86_64.rpm samba-winbind-modules-4.2.10-7.el7_2.i686.rpm samba-winbind-modules-4.2.10-7.el7_2.x86_64.rpm
Red Hat Enterprise Linux Client Optional (v. 7):
noarch: samba-pidl-4.2.10-7.el7_2.noarch.rpm
x86_64: libsmbclient-devel-4.2.10-7.el7_2.i686.rpm libsmbclient-devel-4.2.10-7.el7_2.x86_64.rpm libwbclient-devel-4.2.10-7.el7_2.i686.rpm libwbclient-devel-4.2.10-7.el7_2.x86_64.rpm samba-4.2.10-7.el7_2.x86_64.rpm samba-dc-4.2.10-7.el7_2.x86_64.rpm samba-dc-libs-4.2.10-7.el7_2.x86_64.rpm samba-debuginfo-4.2.10-7.el7_2.i686.rpm

Read the Full Advisory


Advisory ID: RHSA-2016:1486-01
Product: Red Hat Enterprise Linux
Advisory URL: https://access.redhat.com/errata/RHSA-2016:1486.html
Issue date: 2016-07-26

Topic

An update for samba is now available for Red Hat Enterprise Linux 7.Red Hat Product Security has rated this update as having a security impactof Moderate. A Common Vulnerability Scoring System (CVSS) base score, whichgives a detailed severity rating, is available for each vulnerability fromthe CVE link(s) in the References section.

Topics%20covered

Topics Covered

security advisory moderate red hat samba security fix attack DCE/RPC

Relevant Releases Architectures

Red Hat Enterprise Linux Client (v. 7) - noarch, x86_64

Red Hat Enterprise Linux Client Optional (v. 7) - noarch, x86_64

Red Hat Enterprise Linux ComputeNode (v. 7) - noarch, x86_64

Red Hat Enterprise Linux ComputeNode Optional (v. 7) - noarch, x86_64

Red Hat Enterprise Linux Server (v. 7) - noarch, ppc64, ppc64le, s390x, x86_64

Red Hat Enterprise Linux Server Optional (v. 7) - noarch, ppc64, ppc64le, s390x, x86_64

Red Hat Enterprise Linux Server Resilient Storage (v. 7) - x86_64

Red Hat Enterprise Linux Workstation (v. 7) - noarch, x86_64

Red Hat Enterprise Linux Workstation Optional (v. 7) - noarch, x86_64

Bugs Fixed

1350759 - idmap_hash module works incorrectly when used with other backend modules

1351260 - net ads join throws "Failed to join domain: failed to set machine kerberos encryption types: Insufficient access"

1351955 - CVE-2016-2119 samba: Client side SMB2/3 required signing can be downgraded

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