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.