In Xpdf 4.05 (and earlier), a PDF object loop in the PDF resources leads to infinite recursion and a stack overflow. https://www.xpdfreader.com/security-bug/object-loops.html
Created xpdf tracking bugs for this issue: Affects: epel-7 [bug 2279471] Affects: epel-8 [bug 2279472] Affects: fedora-all [bug 2279473]