The relay attack is pretty wild but it also sounds like all these years later all these cars are mostly using an ancient cipher. The Cipher was broken so badly

The relay attack is pretty wild but it also sounds like all these years later all these cars are mostly using an ancient cipher. The Cipher was broken so badly that as far back as 2005 it was published how to break it, and it has still never been changed. If you have regular access to the car (parking garage) you can just break the cipher if you see it on more than one day... no need to relay at all, and no protections against the relay attack would stop it from working. It's a 40-bit cipher but because of a weakness you can calculate down to 2^16 possible keys and then come back on another day and break it very quickly at which point you've essentially got your own key to the car.