How to find out what this script is doing?

Question

linux

I was on a business trip for 2 months without the Internet, today I decided to get in, but in the logs of the server this is what a sheet, it was not me who entered it all, and only I know the password, it is extremely difficult to pick up (regenerated by a 15 character generator), tell me plzz what they did with the server .
referring to the logs
removed his piece
PS Sorry for the sheet, as the spoiler is put, I did not find it.

Answer 1

Judging by

269  [2014-08-10 14:27:32] git clone https://github.com/vanhauser-thc/thc-hydra.git
  270  [2014-08-10 14:27:43] ./configure
  271  [2014-08-10 14:27:51] make
  272  [2014-08-10 14:28:14] make install
  273  [2014-08-10 14:28:17] hydra

you are being used to crack passwords at least

Answer 2

Your password is not really as difficult as you think. You lit it up somewhere else or it hangs in your mail in a letter from the hoster.
Some amateur brute force ssh passwords. It's also lucky that you didn't get the most serious cool hacker, then you wouldn't know for a couple of years that someone else is using the server.
Change the password, disable root login (it is a good idea to do this as soon as any server is installed), reboot the server and see what `ps aux` and web server configs write. It is unlikely that there will be something working.
But if you take the problem seriously, then with any suspicion of hacking, they do a system reinstall, this is the fastest and most effective way to treat any wickedness.