RHSA-2013:0769 - Security Advisory

Topic

Updated glibc packages that fix two security issues and two bugs are now
available for Red Hat Enterprise Linux 5.

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.

Description

The glibc packages provide the standard C libraries (libc), POSIX thread
libraries (libpthread), standard math libraries (libm), and the Name Server
Caching Daemon (nscd) used by multiple programs on the system. Without
these libraries, the Linux system cannot function correctly.

It was found that getaddrinfo() did not limit the amount of stack memory
used during name resolution. An attacker able to make an application
resolve an attacker-controlled hostname or IP address could possibly cause
the application to exhaust all stack memory and crash. (CVE-2013-1914)

A flaw was found in the regular expression matching routines that process
multibyte character input. If an application utilized the glibc regular
expression matching mechanism, an attacker could provide specially-crafted
input that, when processed, would cause the application to crash.
(CVE-2013-0242)

This update also fixes the following bugs:

• The improvements RHSA-2012:1207 made to the accuracy of floating point

functions in the math library caused performance regressions for those
functions. The performance regressions were analyzed and a fix was applied
that retains the current accuracy but reduces the performance penalty to
acceptable levels. Refer to Red Hat Knowledge solution 229993, linked
to in the References, for further information. (BZ#950535)

• It was possible that a memory location freed by the localization code

could be accessed immediately after, resulting in a crash. The fix ensures
that the application does not crash by avoiding the invalid memory access.
(BZ#951493)

Users of glibc 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 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 ia64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 5.9 i386
• Red Hat Enterprise Linux Server - AUS 5.9 ia64
• Red Hat Enterprise Linux Server - AUS 5.9 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 5.9 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 5.9 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386
• Red Hat Enterprise Linux Server - AUS 5.9 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.9 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 5.9 i386

Fixes

• BZ - 905874 - CVE-2013-0242 glibc: Buffer overrun (DoS) in regexp matcher by processing multibyte characters
• BZ - 947882 - CVE-2013-1914 glibc: Stack (frame) overflow in getaddrinfo() when processing entry mapping to long list of address structures

CVEs

• CVE-2013-0242
• CVE-2013-1914

References

• https://access.redhat.com/security/updates/classification/#low
• https://rhn.redhat.com/errata/RHSA-2012-1207.html
• https://access.redhat.com/site/solutions/229993