The ReadCAPTIONImage function in coders/caption.c in ImageMagick 7.0.7-3 allows remote attackers to cause a denial of service (infinite loop) via a crafted font file.
https://usn.ubuntu.com/3681-1/
https://lists.debian.org/debian-lts-announce/2020/09/msg00007.html
https://lists.debian.org/debian-lts-announce/2019/05/msg00015.html