samba4 security update

CentOS Errata and Security Advisory CESA-2013:0506

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.

A flaw was found in the Samba suite’s Perl-based DCE/RPC IDL (PIDL)
compiler, used to generate code to handle RPC calls. This could result in
code generated by the PIDL compiler to not sufficiently protect against
buffer overflows. (CVE-2012-1182)

The samba4 packages have been upgraded to upstream version 4.0.0, which
provides a number of bug fixes and enhancements over the previous version.
In particular, improved interoperability with Active Directory (AD)
domains. SSSD now uses the libndr-krb5pac library to parse the Privilege
Attribute Certificate (PAC) issued by an AD Key Distribution Center (KDC).

The Cross Realm Kerberos Trust functionality provided by Identity
Management, which relies on the capabilities of the samba4 client library,
is included as a Technology Preview. This functionality and server
libraries, is included as a Technology Preview. This functionality uses the
libndr-nbt library to prepare Connection-less Lightweight Directory Access
Protocol (CLDAP) messages.

Additionally, various improvements have been made to the Local Security
Authority (LSA) and Net Logon services to allow verification of trust
from a Windows system. Because the Cross Realm Kerberos Trust functionality
is considered a Technology Preview, selected samba4 components are
considered to be a Technology Preview. For more information on which Samba
packages are considered a Technology Preview, refer to Table 5.1, “Samba4
Package Support” in the Release Notes, linked to from the References.
(BZ#766333, BZ#882188)

This update also fixes the following bug:

• Prior to this update, if the Active Directory (AD) server was rebooted,
  Winbind sometimes failed to reconnect when requested by “wbinfo -n” or
  “wbinfo -s” commands. Consequently, looking up users using the wbinfo tool
  failed. This update applies upstream patches to fix this problem and now
  looking up a Security Identifier (SID) for a username, or a username for a
  given SID, works as expected after a domain controller is rebooted.
  (BZ#878564)

All users of samba4 are advised to upgrade to these updated packages,
which fix these issues and add these enhancements.

Warning: If you upgrade from Red Hat Enterprise Linux 6.3 to Red Hat
Enterprise Linux 6.4 and you have Samba in use, you should make sure that
you uninstall the package named “samba4” to avoid conflicts during the
upgrade.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2013-March/081660.html
https://lists.centos.org/pipermail/centos-cr-announce/2013-February/026959.html

Affected packages:
samba4
samba4-client
samba4-common
samba4-dc
samba4-dc-libs
samba4-devel
samba4-libs
samba4-pidl
samba4-python
samba4-swat
samba4-test
samba4-winbind
samba4-winbind-clients
samba4-winbind-krb5-locator

Upstream details at:
https://access.redhat.com/errata/RHSA-2013:0506