ImageMagick 7.0.6-1 has an out-of-bounds read vulnerability in ReadOneMNGImage in coders/png.c.
https://www.debian.org/security/2017/dsa-4040
https://www.debian.org/security/2017/dsa-4019
https://usn.ubuntu.com/3681-1/
https://github.com/ImageMagick/ImageMagick/issues/542
https://github.com/ImageMagick/ImageMagick/commit/307fa45d512641fcd105f0d57ca50c1437cd1b81