I was driving on a highway using the cars adaptive cruise control, when the car suddenly without warning slammed on the brakes. This caused me to be rear ended by a car behind me. The automatic emergency braking system had triggered without any hazard in front of me. Although there had not been a warning light of a malfunction, the car had previously activated phantom emergency braking. Previously the car on several occasions the cars AEB system activated but only briefly applied the brakes before quickly disengaging and the AEB warning went away. However, this time the brakes fully activated causing the car to stop abruptly from 50-60mph to a stop. I have not yet reported the issue to the dealer and no one has yet inspected the vehicle. Although no one was hurt, this issue could have caused very serious injuries and did cause significant damage to my vehicle and the other vehicle.