The package allows you to snoop on login tty’s through another tty-device or pseudo-tty. The snoop-tty becomes a ‘clone’ of the original tty, redirecting both input and output from/to it.
You can download it from the following link: https://packetstormsecurity.com/files/download/12865/ttysnoop-0.12c.tar.gz
Source: https://packetstormsecurity.com/files/12865/ttysnoop-0.12c.tar.gz.html