Hi everyone,
I just downloaded ubuntu server edition (LTS) yesterday as my first pure linux operating system and I'm having trouble with a blatant security problem in SSH. When I connect to the server from terminal on my mac everything works perfectly, only it's too perfect. My problem is with the fact that SSH allows me to switch to the root user on the server even though I blocked it in the SSHD_config file already. If anyone knows how to block the SU command or just stop SSH users from switching accounts that'd be great.

Thanks in advance