Fwiw, here's the wiki re: Security hackers:
https://en.wikipedia.org/wiki/Security_hacker
Note: point one of post number 4 of the following old CFC Chat Forum thread is a brief explanation by an Administrator of hacking attempts this CFC Discussion Board has faced (not even initiated by a human hacker) - gives an inkling as to what a potential pain they can be:
http://www.chesscanada.info/forum/sh...8993#post28993