Globus Toolkit 3.2.x, 4.0.x, and 4.1.0 before 20060815 allow local users to obtain sensitive information (proxy certificates) and overwrite arbitrary files via a symlink attack on temporary files in the /tmp directory, as demonstrated by files created by (1) myproxy-admin-adduser, (2) grid-ca-sign, and (3) grid-security-config.