Low: glibc security, bug fix, and enhancement update

Updated glibc packages that fix two security issues, several bugs, and add
various enhancements are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having low
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.

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.

A flaw was found in the way the ldd utility identified dynamically linked
libraries. If an attacker could trick a user into running ldd on a
malicious binary, it could result in arbitrary code execution with the
privileges of the user running ldd. (CVE-2009-5064)

It was found that the glibc addmntent() function, used by various mount
helper utilities, did not handle certain errors correctly when updating the
mtab (mounted file systems table) file. If such utilities had the setuid
bit set, a local attacker could use this flaw to corrupt the mtab file.
(CVE-2011-1089)

Red Hat would like to thank Dan Rosenberg for reporting the CVE-2011-1089
issue.

This update also fixes several bugs and adds various enhancements.
Documentation for these bug fixes and enhancements will be available
shortly from the Technical Notes document, linked to in the References
section.

Users are advised to upgrade to these updated glibc packages, which contain
backported patches to resolve these issues and add these enhancements.

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/kb/docs/DOC-11259

676467 - glibc-debuginfo.i686 and glibc-debuginfo.x86_64 conflict
688980 - CVE-2011-1089 glibc: Suid mount helpers fail to anticipate RLIMIT_FSIZE
692393 - CVE-2009-5064 glibc: ldd unexpected code execution issue
694386 - POWER4 strncmp crashes reading past zero byte
700507 - nscd start produce USER_AVC
706903 - getpwuid unreliable when using NIS, missing flag: -DUSE_BINDINGDIR=1
711987 - [RHEL-6] statvfs tries to stat unrelated mountpoints
712248 - getconf returns incorrect FILESIZEBITS for Lustre filesystem
713134 - CVE-2009-5064 glibc: ldd unexpected code execution issue [rhel-6.2]
714823 - getaddrinfo returns PTR name in ai_canonname when using DNS
729036 - Debuginfo package issues in glibc
730379 - libresolv is not compiled with the stack protector enabled
731042 - pthread_create dumps core when it fails to set real time policy
736346 - make initgroups (setgroups) thread aware
737778 - setlocale() fails if LC_CTYPE is set to Turkish locale
738665 - strange pthread/fork deadlock
738763 - need to add IP_MULTICAST_ALL option to glibc headers
739184 - Statically-linked binaries that call gethostbyname crash when executed.

https://www.redhat.com/security/data/cve/CVE-2009-5064.html
https://www.redhat.com/security/data/cve/CVE-2011-1089.html
https://access.redhat.com/security/updates/classification/#low
https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/6.2_Technical_Notes/glibc.html#RHSA-2011-1526