ispell before 3.1.20 allows local users to overwrite files of other users via a symlink attack on a temporary file.
http://www.redhat.com/support/errata/RHSA-2001-074.html
http://www.linux-mandrake.com/en/security/2001/MDKSA-2001-058.php3
http://marc.info/?l=bugtraq&m=99317439131174&w=2
http://download.immunix.org/ImmunixOS/6.2/updates/IMNX-2001-62-004-01