Finally rooted, the machine was very easy, but due to the instability and all the users that cause the 503 it was frustrating on the free server. Tips:
User - I’ts all about google around exploits, don’t stop only on exploitdb, look on youtube, on blogs, there is a lot of material online. (A little tip, if you have problems with the common rev shell, use meterpreter)
Root: it took me 5 seconds, just do the most common things you do after logging into a machine, no script is ever needed