(RHSA-2004:249) libpng security update

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

During an audit of Red Hat Linux updates, the Fedora Legacy team found a
security issue in libpng that had not been fixed in Red Hat Enterprise
Linux 3. An attacker could carefully craft a PNG file in such a way that
it would cause an application linked to libpng to crash or potentially
execute arbitrary code when opened by a victim.

Note: this issue does not affect Red Hat Enterprise Linux 2.1

Users are advised to upgrade to these updated packages that contain a
backported security fix and are not vulnerable to this issue.