Fabric before 1.1.0 allows local users to overwrite arbitrary files via a symlink attack on (1) a /tmp/fab.*.tar file or (2) certain other files in the top level of /tmp/.
https://bugzilla.redhat.com/show_bug.cgi?id=710462
http://www.openwall.com/lists/oss-security/2011/06/06/12
http://www.openwall.com/lists/oss-security/2011/06/03/5
http://lists.fedoraproject.org/pipermail/package-announce/2011-July/062534.html
http://code.fabfile.org/projects/fabric/files/Fabric-1.1.0.tar.gz