(RHSA-2013:0508) Low: sssd security, bug fix and enhancement update

The System Security Services Daemon (SSSD) provides a set of daemons to
manage access to remote directories and authentication mechanisms. It
provides an NSS and PAM interface toward the system and a pluggable
back-end system to connect to multiple different account sources. It is
also the basis to provide client auditing and policy services for projects
such as FreeIPA.

A race condition was found in the way SSSD copied and removed user home
directories. A local attacker who is able to write into the home directory
of a different user who is being removed could use this flaw to perform
symbolic link attacks, possibly allowing them to modify and delete
arbitrary files with the privileges of the root user. (CVE-2013-0219)

Multiple out-of-bounds memory read flaws were found in the way the autofs
and SSH service responders parsed certain SSSD packets. An attacker could
spend a specially-crafted packet that, when processed by the autofs or SSH
service responders, would cause SSSD to crash. This issue only caused a
temporary denial of service, as SSSD was automatically restarted by the
monitor process after the crash. (CVE-2013-0220)

The CVE-2013-0219 and CVE-2013-0220 issues were discovered by Florian
Weimer of the Red Hat Product Security Team.

These updated sssd packages also include numerous bug fixes and
enhancements. Space precludes documenting all of these changes in this
advisory. Users are directed to the Red Hat Enterprise Linux 6.4 Technical
Notes, linked to in the References, for information on the most significant
of these changes.

All SSSD users are advised to upgrade to these updated packages, which
upgrade SSSD to upstream version 1.9 to correct these issues, fix these
bugs and add these enhancements.