Important: kernel security update

Updated kernel packages that fix one security issue are now available for
Red Hat Enterprise Linux 4.7 Extended Update Support.

The Red Hat Security Response Team has rated this update as having
important security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from the
CVE link in the References section.

The kernel packages contain the Linux kernel, the core of any Linux
operating system.

This update fixes the following security issue:

* When an application has a stack overflow, the stack could silently
overwrite another memory mapped area instead of a segmentation fault
occurring, which could cause an application to execute arbitrary code,
possibly leading to privilege escalation. It is known that the X Window
System server can be used to trigger this flaw. (CVE-2010-2240, Important)

Red Hat would like to thank the X.Org security team for reporting this
issue. Upstream acknowledges Rafal Wojtczuk as the original reporter.

Users should upgrade to these updated packages, which contain backported
patches to correct this issue. The system must be rebooted for this update
to take effect.

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
http://kbase.redhat.com/faq/docs/DOC-11259

To install kernel packages manually, use "rpm -ivh [package]". Do not
use "rpm -Uvh" as that will remove the running kernel binaries from
your system. You may use "rpm -e" to remove old kernels after
determining that the new kernel functions properly on your system.

606611 - CVE-2010-2240 kernel: mm: keep a guard page below a grow-down stack segment

https://www.redhat.com/security/data/cve/CVE-2010-2240.html
http://www.redhat.com/security/updates/classification/#important