FacePunch has implemented a new anti-cheat system for Rust and it has already banned 4621 players.
A message from FacePunch about the anti-cheat system called "Cheat Punch":
"We're testing it out on our official servers to make sure it all works before forcing it on everyone else."
"If you get kicked from the official servers with the message that you’ve been banned then you have been caught, you know what you have done. You won’t get unbanned. We know it was your 9 year old cousin.
We know your computer got hijacked. We know that the CIA is getting you banned from all your games on Steam so you will join them in the hunt for aliens."
Even though it already took care of this many cheaters, FacePunch says this is a "stop-gap" solution and that it is not hard to get around. They will continue working on creating more anti-cheat measures in the future.