RHSA-2014:0383 - Security Advisory

Topic

Updated samba4 packages that fix three security issues are now available
for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having Moderate
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

Description

Samba is an open-source implementation of the Server Message Block (SMB) or
Common Internet File System (CIFS) protocol, which allows PC-compatible
machines to share files, printers, and other information.

It was found that certain Samba configurations did not enforce the password
lockout mechanism. A remote attacker could use this flaw to perform
password guessing attacks on Samba user accounts. Note: this flaw only
affected Samba when deployed as a Primary Domain Controller.
(CVE-2013-4496)

A flaw was found in Samba's "smbcacls" command, which is used to set or get
ACLs on SMB file shares. Certain command line options of this command would
incorrectly remove an ACL previously applied on a file or a directory,
leaving the file or directory without the intended ACL. (CVE-2013-6442)

A flaw was found in the way the pam_winbind module handled configurations
that specified a non-existent group as required. An authenticated user
could possibly use this flaw to gain access to a service using pam_winbind
in its PAM configuration when group restriction was intended for access to
the service. (CVE-2012-6150)

Red Hat would like to thank the Samba project for reporting CVE-2013-4496
and CVE-2013-6442, and Sam Richardson for reporting CVE-2012-6150.
Upstream acknowledges Andrew Bartlett as the original reporter of
CVE-2013-4496, and Noel Power as the original reporter of CVE-2013-6442.

All users of Samba are advised to upgrade to these updated packages, which
contain backported patches to correct these issues. After installing this
update, the smb service will be restarted automatically.

Solution

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to use the
Red Hat Network to apply this update are available at
https://access.redhat.com/site/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.5 i386
• Red Hat Enterprise Linux Server - AUS 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.5 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.5 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.5 i386
• Red Hat Enterprise Linux EUS Compute Node 6.5 x86_64
• Red Hat Enterprise Linux Server - TUS 6.5 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 1036897 - CVE-2012-6150 samba: pam_winbind fails open when non-existent group specified to require_membership_of
• BZ - 1044099 - CVE-2013-6442 samba: smbcacls will delete ACL lists in certain circumstances
• BZ - 1072792 - CVE-2013-4496 samba: Password lockout not enforced for SAMR password changes

CVEs

• CVE-2013-4496
• CVE-2012-6150
• CVE-2013-6442

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://www.samba.org/samba/security/CVE-2012-6150
• https://www.samba.org/samba/security/CVE-2013-4496
• https://www.samba.org/samba/security/CVE-2013-6442