RHSA-2013:0663 - Security Advisory

Topic

Updated sssd packages that fix one security issue and two bugs are now
available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate
security impact. A Common Vulnerability Scoring System (CVSS) base score,
which gives a detailed severity rating, is available from the CVE link in
the References section.

Description

SSSD (System Security Services Daemon) provides a set of daemons to manage
access to remote directories and authentication mechanisms. It provides
NSS (Name Service Switch) and PAM (Pluggable Authentication Modules)
interfaces toward the system and a pluggable back end system to connect to
multiple different account sources.

When SSSD was configured as a Microsoft Active Directory client by using
the new Active Directory provider (introduced in RHSA-2013:0508), the
Simple Access Provider ("access_provider = simple" in
"/etc/sssd/sssd.conf") did not handle access control correctly. If any
groups were specified with the "simple_deny_groups" option (in sssd.conf),
all users were permitted access. (CVE-2013-0287)

The CVE-2013-0287 issue was discovered by Kaushik Banerjee of Red Hat.

This update also fixes the following bugs:

• If a group contained a member whose Distinguished Name (DN) pointed out

of any of the configured search bases, the search request that was
processing this particular group never ran to completion. To the user, this
bug manifested as a long timeout between requesting the group data and
receiving the result. A patch has been provided to address this bug and
SSSD now processes group search requests without delays. (BZ#907362)

• The pwd_expiration_warning should have been set for seven days, but

instead it was set to zero for Kerberos. This incorrect zero setting
returned the "always display warning if the server sends one" error message
and users experienced problems in environments like IPA or Active
Directory. Currently, the value setting for Kerberos is modified and this
issue no longer occurs. (BZ#914671)

All users of sssd are advised to upgrade to these updated packages, which
contain backported patches to correct these issues.

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/knowledge/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 6.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.4 i386
• Red Hat Enterprise Linux Server - AUS 6.4 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 6.4 s390x
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.4 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 6.4 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.4 i386
• Red Hat Gluster Storage Server for On-premise 2.1 x86_64
• Red Hat Storage for Public Cloud (via RHUI) 2.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x

Fixes

• BZ - 910938 - CVE-2013-0287 sssd: simple access provider flaw prevents intended ACL use when client to an AD provider
• BZ - 914671 - pwd_expiration_warning has wrong default for Kerberos

CVEs

• CVE-2013-0287

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://rhn.redhat.com/errata/RHSA-2013-0508.html