The function GfxImageColorMap::getGray in GfxState.cc in Poppler 0.54.0 allows remote attackers to cause a denial of service (stack-based buffer over-read and application crash) via a crafted PDF document, related to missing color-map validation in ImageOutputDev.cc.
https://www.debian.org/security/2018/dsa-4079
https://usn.ubuntu.com/4042-1/
https://security.gentoo.org/glsa/201801-17
https://bugs.freedesktop.org/show_bug.cgi?id=100774
http://somevulnsofadlab.blogspot.com/2017/06/popplerstack-buffer-overflow-in.html