The libpng packages contain a library of functions for creating andmanipulating PNG (Portable Network Graphics) image format files.A heap-based buffer overflow flaw was found in the way libpng processedcompressed chunks in PNG image files. An attacker could create aspecially-crafted PNG image file that, when opened, could cause anapplication using libpng to crash or, possibly, execute arbitrary code withthe privileges of the user running the application. (CVE-2011-3045)Users of libpng should upgrade to these updated packages, which correctthis issue. For Red Hat Enterprise Linux 5, they contain a backportedpatch. For Red Hat Enterprise Linux 6, they upgrade libpng to version1.2.48. All running applications using libpng must be restarted for theupdate to take effect.