Use-after-free vulnerability in the DestroyImage function in image.c in ImageMagick before 7.0.6-6 allows remote attackers to cause a denial of service via a crafted file.
https://www.debian.org/security/2017/dsa-4074
https://www.debian.org/security/2017/dsa-4040
https://usn.ubuntu.com/3681-1/
https://security.gentoo.org/glsa/201711-07
https://github.com/ImageMagick/ImageMagick/commit/04178de2247e353fc095846784b9a10fefdbf890
https://blogs.gentoo.org/ago/2017/08/10/imagemagick-use-after-free-in-destroyimage-image-c/