pip before 1.3 allows local users to overwrite arbitrary files via a symlink attack on a file in the /tmp/pip-build temporary directory.
lists.fedoraproject.org/pipermail/package-announce/2013-May/105952.html
lists.fedoraproject.org/pipermail/package-announce/2013-May/105989.html
lists.fedoraproject.org/pipermail/package-announce/2013-May/106311.html
www.openwall.com/lists/oss-security/2013/03/22/10
github.com/pypa/pip/issues/725
github.com/pypa/pip/pull/734/files
github.com/pypa/pip/pull/780/files