I guess passport is the anti hack for Urt 4.2 though I'm not really sure about the details. Actually if anyone had info. about passport it would be great if you shared.
There are a couple threads about this on the UrT forums... but here is the gist as I understand it.
UrT will now be a register service the same way that games like combat arms are... you get an account and that account is yours. So when you log into 4.2 you should have to put in that verified account details not just pick a name and a server randomly. Part of how that works with the anti-cheat is that they are tracking user accounts... so if you get banned it gets reported to your account (hopefully banning the user from making more accounts and just coming back with another name).
Your passport is also your access to the UrT forums... so it maintains an identity across game and forums.
We won't know until we have 4.2 in our grubby little hands... but that is basically what I understand... and would be most logical.
Not a failsafe, but certainly an improvement.