libpng security update

Updated libpng packages that fix a security issue are now available for Red
Hat Enterprise Linux 4.

This update has been rated as having moderate security impact by the Red
Hat Security Response Team.

The libpng package contains a library of functions for creating and
manipulating PNG (Portable Network Graphics) image format files.

A heap based buffer overflow bug was found in the way libpng strips alpha
channels from a PNG image. An attacker could create a carefully crafted PNG
image file in such a way that it could cause an application linked with
libpng to crash or execute arbitrary code when the file is opened by a
victim. The Common Vulnerabilities and Exposures project has assigned the
name CVE-2006-0481 to this issue.

Please note that the vunerable libpng function is only used by TeTeX and
XEmacs on Red Hat Enterprise Linux 4.

All users of libpng are advised to update to these updated packages which
contain a backported patch that is not vulnerable to this issue.

Before applying this update, make sure all previously released errata
relevant to your system have been applied.

This update is available via Red Hat Network. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

179455 - CVE-2006-0481 libpng heap based buffer overflow

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-0481