A heap-based buffer overflow flaw was found in the way libpng processed tEXt chunks in PNG image files. An attacker could create a specially-crafted PNG image file that, when opened, could cause an application using libpng to crash or, possibly, execute arbitrary code with the privileges of the user running the application. (CVE-2011-3048)
Run yum update libpng to update your system.
i686: libpng-devel-1.2.49-1.12.amzn1.i686 libpng-static-1.2.49-1.12.amzn1.i686 libpng-debuginfo-1.2.49-1.12.amzn1.i686 libpng-1.2.49-1.12.amzn1.i686 src: libpng-1.2.49-1.12.amzn1.src x86_64: libpng-static-1.2.49-1.12.amzn1.x86_64 libpng-1.2.49-1.12.amzn1.x86_64 libpng-debuginfo-1.2.49-1.12.amzn1.x86_64 libpng-devel-1.2.49-1.12.amzn1.x86_64