Hacking the technology in a Tesla car is almost becoming its own sub-genre of cyber-attacks. This one exploits the technology used in the electronic key fob.
NFC Relay Attack on TESLA Model Y (ioactive.com)
A relay attack is where the hacker stands behind you in the petrol station queue, although why a Tesla driver would be buying petrol is a good question, with a radio transmitter that will re-transmit your key fob’s security information to another hacker standing by your car, with a receiver that impersonates your key.
Using NFC as opposed to Bluetooth was supposed to defend against radio relay attacks as it has a much-reduced range so making the radio relay more difficult, but obviously now, not impossible. It is not an easy attack, and the paper is only a proof of concept, not an actual attack in the wild.
What you need to do – and what I have done – is get a radio-proof wallet for your key fob – search RFID key pouch.
Clive Catton MSc (Cyber Security) – by-line and other articles