Over the past few years, owners of cars with keyless start systems have learned to worry about so-called relay attacks, in which hackers exploit radio-enabled keys to steal vehicles without leaving a trace.
https://www.wired.com/story/hackers-can-clone-millions-of-toyota-hyundai-kia-keys/
https://www.wired.com/story/hackers-can-clone-millions-of-toyota-hyundai-kia-keys/