Newly released security update upgrading xpdf to version xpdf-0.91-1.5x
is using in defaults file /usr/share/fonts/default/Type1/ path which
does not exist on 5.x systems. This should be instead
Leaving app-defaults file untouched leads to a "Segmentation fault"
on a startup. After corrections xpdf works as expected.
It's fixed in xpdf-0.91-2.5x. You will find it in errata soon.