Can using sudo provide Defense in Depth benefits?
With a typical configuration the use of sudo provides no real protection. The user either enters their own password or the root password to gain full root access, in either case the attacker can exploit their session and get the password. A session exploit can be easily arranged by creating a shell function or alias that makes sudo run something else (such as using netcat to send the password out over the network). One way of making this sort of attack more difficult is to make root own the user home directory, files such as ~/.login that are used by the user shell, the ~/.ssh directory and the ~/.ssh/authorized_keys file. This way a hostile party can’t change the configuration, so a successful attack has to involve a long running process that uses ptrace to intercept the shell and divert an attempt to run sudo. If the non-root user is prevented from using ptrace then things start to become a little more difficult for the attacker. In some quick tests I was able to capture about half t
