The security update for glibc (glibc-2.5-58.el5_6.2) introduced a new bug when expanding the dynamic string tokens.  This update (glibc-2.5-58.el5_6.3) resolves this known issue.

* When expanding the dynamic string tokens in load paths for the dynamic linker
or in module names for the "dlopen" function, previous versions of the glibc
libraries may have failed to allocate enough memory for the expanded strings,
causing certain applications to terminate unexpectedly with the following error:

malloc(): memory corruption: 0x09b43fd0

With this update, the underlying source code has been adapted to allocate enough
memory for the expanded strings, and the glibc libraries no longer cause
applications to crash. (BZ#695258)

SL 5.x
     SRPMS:
         glibc-2.5-58.el5_6.3.src.rpm

     i386:
         glibc-2.5-58.el5_6.3.i386.rpm
         glibc-2.5-58.el5_6.3.i686.rpm
         glibc-common-2.5-58.el5_6.3.i386.rpm
         glibc-devel-2.5-58.el5_6.3.i386.rpm
         glibc-headers-2.5-58.el5_6.3.i386.rpm
         glibc-utils-2.5-58.el5_6.3.i386.rpm
         nscd-2.5-58.el5_6.3.i386.rpm

     x86_64:
         glibc-2.5-58.el5_6.3.i686.rpm
         glibc-2.5-58.el5_6.3.x86_64.rpm
         glibc-common-2.5-58.el5_6.3.x86_64.rpm
         glibc-devel-2.5-58.el5_6.3.i386.rpm
         glibc-devel-2.5-58.el5_6.3.x86_64.rpm
         glibc-headers-2.5-58.el5_6.3.x86_64.rpm
         glibc-utils-2.5-58.el5_6.3.x86_64.rpm
         nscd-2.5-58.el5_6.3.x86_64.rpm

- Scientific Linux Development Team

=-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-==-=

Synopsis:   Important: glibc security update
Issue date: 2011-04-04
CVE Names:  CVE-2011-0536
             CVE-2011-1071
             CVE-2011-1095

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 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.

SL 5.x
     SRPMS:
         glibc-2.5-58.el5_6.2.src.rpm

     i386:
         glibc-2.5-58.el5_6.2.i386.rpm
         glibc-2.5-58.el5_6.2.i686.rpm
         glibc-common-2.5-58.el5_6.2.i386.rpm
         glibc-devel-2.5-58.el5_6.2.i386.rpm
         glibc-headers-2.5-58.el5_6.2.i386.rpm
         glibc-utils-2.5-58.el5_6.2.i386.rpm
         nscd-2.5-58.el5_6.2.i386.rpm

     x86_64:
         glibc-2.5-58.el5_6.2.i686.rpm
         glibc-2.5-58.el5_6.2.x86_64.rpm
         glibc-common-2.5-58.el5_6.2.x86_64.rpm
         glibc-devel-2.5-58.el5_6.2.i386.rpm
         glibc-devel-2.5-58.el5_6.2.x86_64.rpm
         glibc-headers-2.5-58.el5_6.2.x86_64.rpm
         glibc-utils-2.5-58.el5_6.2.x86_64.rpm
         nscd-2.5-58.el5_6.2.x86_64.rpm

- Scientific Linux Development Team