pspy is a command line tool designed to snoop on processes without need for root permissions. It allows you to see commands run by other users, cron jobs, etc. as they execute. Great for enumeration of Linux systems in CTFs. Also great to demonstrate your colleagues why passing secrets as arguments on the command line is a bad idea.
source: https://github.com/DominicBreuker/pspy
Privilege escalation involved exploiting a bug, design flaw or misconfiguration to gain elevated access and perform unauthorized actions. For example, escalating from a restrictive shell as user www-data, to a session as root.
example of watching process and sniffing secrets from command, htb example box cache I think