impose in impose+ 0.2 allows local users to overwrite arbitrary files via a symlink attack on (1) /tmp/*-tmp.ps and (2) /tmp/bboxx-* temporary files.
https://bugs.gentoo.org/show_bug.cgi?id=235770
http://www.securityfocus.com/bid/30906
http://www.openwall.com/lists/oss-security/2008/10/30/2