ReadXWDImage in coders/xwd.c in the XWD image parsing component of ImageMagick 7.0.8-41 Q16 allows attackers to cause a denial-of-service (divide-by-zero error) by crafting an XWD image file in which the header indicates neither LSB first nor MSB first.
https://www.debian.org/security/2020/dsa-4712
https://usn.ubuntu.com/4034-1/
https://lists.debian.org/debian-lts-announce/2020/08/msg00030.html
https://github.com/ImageMagick/ImageMagick6/commit/f663dfb8431c97d95682a2b533cca1c8233d21b4
https://github.com/ImageMagick/ImageMagick/issues/1546
http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00001.html
http://lists.opensuse.org/opensuse-security-announce/2019-06/msg00057.html