The (1) gendef.sh, (2) doc/fixinfo.sh, and (3) contrib/gdiffmk/tests/runtests.in scripts in GNU troff (aka groff) 1.21 and earlier allow local users to overwrite arbitrary files via a symlink attack on a gro#####.tmp or /tmp/##### temporary file.
http://www.mandriva.com/security/advisories?name=MDVSA-2013:086
http://www.mandriva.com/security/advisories?name=MDVSA-2013:085
http://openwall.com/lists/oss-security/2009/08/14/5
http://openwall.com/lists/oss-security/2009/08/14/4
http://cvsweb.openwall.com/cgi/cvsweb.cgi/Owl/packages/groff/groff-1.20.1-owl-tmp.diff