In ImageMagick before 6.9.9-0 and 7.x before 7.0.6-1, the ReadOneMNGImage function in coders/png.c has an out-of-bounds read with the MNG CLIP chunk.Referenceshttps://www.debian.org/security/2017/dsa-4040https://usn.ubuntu.com/3681-1/https://security.gentoo.org/glsa/201711-07http://www.securityfocus.com/bid/100494https://www.debian.org/security/2017/dsa-4019https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=870109https://github.com/ImageMagick/ImageMagick/commit/d072ed6aff835c174e856ce3a428163c0da9e8f4
