When ImageMagick 7.0.6-1 processes a crafted file in convert, it can lead to an address access exception in the WritePTIFImage() function in coders/tiff.c.
https://www.debian.org/security/2017/dsa-4040
https://www.debian.org/security/2017/dsa-4019
https://usn.ubuntu.com/3681-1/