libpng is vulnerable to buffer overflows. A malicious user can pass a malicious png file to the system to cause an out-of-bounds read that can lead to the system crashing.
www.securityfocus.com/bid/78624
bugzilla.redhat.com/show_bug.cgi?id=1281756
github.com/glennrp/libpng/commit/1bef8e97995c33123665582e57d3ed40b57d5978
github.com/glennrp/libpng/commit/81f44665cce4cb1373f049a76f3904e981b7a766
github.com/glennrp/libpng/commit/83f4c735c88e7f451541c1528d8043c31ba3b466
github.com/glennrp/libpng/commit/9f2ad4928e47036cf1ac9b8fe45a491f15be2324
github.com/glennrp/libpng/commit/a901eb3ce6087e0afeef988247f1a1aa208cb54d