The ReadWMFImage function in coders/wmf.c in GraphicsMagick 1.3.26 has a use-after-free issue for data associated with exception reporting.
hg.code.sf.net/p/graphicsmagick/code/rev/be898b7c97bd
blogs.gentoo.org/ago/2017/08/05/graphicsmagick-use-after-free-in-readwmfimage-wmf-c/
lists.debian.org/debian-lts-announce/2018/08/msg00002.html
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PF62B5PJA2JDUOCKJGUQO3SPL74BEYSV/
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WHIKB4TP6KBJWT2UIPWL5MWMG5QXKGEJ/
usn.ubuntu.com/4222-1/
www.debian.org/security/2018/dsa-4321