ps -aux or
top, I can list other users running processes, but I'm neither running as root nor making use of
By default, you can always list other users processes in Linux.
To change that, you need to mount
proc /proc proc defaults,hidepid=2
This functionality is supported from the kernel v3.2 onwards. It hides /proc and consequentially
ps activity from all users except root.
Taken from this article about
hidepid=2 - It means hidepid=1 plus all /proc/PID/ will be invisible to other users. It compicates intruder's task of gathering info about running processes, whether some daemon runs with elevated privileges, whether another user runs some sensitive program, whether other users run any program at all, etc.