Finally.
Foothold: DDoS? Really? Check the description before run something!
User: check that same place where you’ve found those creds. Make yourself familiar with capabilities of the service and ask yourself what permissions should you have to view that content.
Root: was mindblowing for me. It’s right in front of your eyes once you logged in, but you just cannot violate args. Fortunately, there is a way to substitute one thing with another and use the same command to get a shell