glibc, nscd security update

CentOS Errata and Security Advisory CESA-2011:0412

The glibc packages contain the standard C libraries used by multiple
programs on the system. These packages contain the standard C and the
standard math libraries. Without these two libraries, a Linux system cannot
function properly.

The fix for CVE-2010-3847 introduced a regression in the way the dynamic
loader expanded the $ORIGIN dynamic string token specified in the RPATH and
RUNPATH entries in the ELF library header. A local attacker could use this
flaw to escalate their privileges via a setuid or setgid program using
such a library. (CVE-2011-0536)

It was discovered that the glibc addmntent() function did not sanitize its
input properly. A local attacker could possibly use this flaw to inject
malformed lines into /etc/mtab via certain setuid mount helpers, if the
attacker were allowed to mount to an arbitrary directory under their
control. (CVE-2010-0296)

It was discovered that the glibc fnmatch() function did not properly
restrict the use of alloca(). If the function was called on sufficiently
large inputs, it could cause an application using fnmatch() to crash or,
possibly, execute arbitrary code with the privileges of the application.
(CVE-2011-1071)

It was discovered that the locale command did not produce properly escaped
output as required by the POSIX specification. If an attacker were able to
set the locale environment variables in the environment of a script that
performed shell evaluation on the output of the locale command, and that
script were run with different privileges than the attacker’s, it could
execute arbitrary code with the privileges of the script. (CVE-2011-1095)

All users should upgrade to these updated packages, which contain
backported patches to correct these issues.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2011-April/079459.html
https://lists.centos.org/pipermail/centos-announce/2011-April/079460.html

Affected packages:
glibc
glibc-common
glibc-devel
glibc-headers
glibc-utils
nscd

Upstream details at:
https://access.redhat.com/errata/RHSA-2011:0412