I read about this in the Silence on the Wire by Michal Zalewski. And you don't need a fullblown AI, a good statistical model is enough to make a guess on passwords, and if you have a bunch of probabilities to cut down your search space to a more probable set. And the book is from 2005, so I wouldn't say it is new. <a href="https://nostarch.com/silence.htm" rel="nofollow noreferrer">https://nostarch.com/silence.htm</a><p>I even remember reading about how Clifford Stoll recognized the different attackers by "typing rhythm" in Cuckoo's Egg.