jhead.c in Matthias Wandel jhead 2.84 and earlier allows local users to overwrite arbitrary files via a symlink attack on a temporary file.
https://bugs.launchpad.net/ubuntu/+source/jhead/+bug/271020
http://www.openwall.com/lists/oss-security/2009/02/06/5
http://www.openwall.com/lists/oss-security/2008/10/16/3