Catalog.cc in Xpdf 4.02 has a NULL pointer dereference because Catalog.pageLabels is initialized too late in the Catalog constructor.
https://forum.xpdfreader.com/viewtopic.php?f=3&t=41890
http://packetstormsecurity.com/files/154713/Xpdf-4.02-NULL-Pointer-Dereference.html