An issue was discovered in Poppler 0.74.0. There is a heap-based buffer over-read in the function PSOutputDev::checkPageSlice at PSOutputDev.cc.
https://lists.debian.org/debian-lts-announce/2019/10/msg00025.html
https://lists.debian.org/debian-lts-announce/2019/10/msg00024.html
https://gitlab.freedesktop.org/poppler/poppler/issues/751