The ReadMNGImage function in coders/png.c in GraphicsMagick 1.3.26 mishandles large MNG images, leading to an invalid memory read in the SetImageColorCallBack function in magick/image.c.Referenceshttps://blogs.gentoo.org/ago/2017/08/05/graphicsmagick-invalid-memory-read-in-setimagecolorcallback-image-c/http://hg.code.sf.net/p/graphicsmagick/code/rev/cd699a44f188https://www.debian.org/security/2018/dsa-4321https://lists.debian.org/debian-lts-announce/2018/08/msg00002.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PF62B5PJA2JDUOCKJGUQO3SPL74BEYSV/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WHIKB4TP6KBJWT2UIPWL5MWMG5QXKGEJ/https://usn.ubuntu.com/4222-1/
