ReadOneJNGImage in coders/png.c in GraphicsMagick version 1.3.26 does not properly validate JNG data, leading to a denial of service (assertion failure in magick/pixel_cache.c, and application crash).
hg.code.sf.net/p/graphicsmagick/code/rev/358608a46f0a
www.securityfocus.com/bid/100958
blogs.gentoo.org/ago/2017/09/19/graphicsmagick-assertion-failure-in-pixel_cache-c/
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PF62B5PJA2JDUOCKJGUQO3SPL74BEYSV/
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WHIKB4TP6KBJWT2UIPWL5MWMG5QXKGEJ/
sourceforge.net/p/graphicsmagick/bugs/439/
usn.ubuntu.com/4232-1/