os._execvpe from os.py in Python 2.2.1 and earlier creates temporary files with predictable names, which could allow local users to execute arbitrary code via a symlink attack.
http://marc.info/?l=bugtraq&m=104333092200589&w=2
http://www.debian.org/security/2002/dsa-159
http://www.iss.net/security_center/static/10009.php