The contact owns a 2017 Genesis G90. The contact stated while the vehicle was turned off, locked, and parked in the driveway, he pressed the trunk release button on the key fob to open the trunk while he was standing behind the vehicle. However, the vehicle inadvertently rolled backward independently, and hit the contact, causing him to flip up in the air, and the contact fell down at the curb on the driver's side of the driveway. The vehicle continued to roll down, rolled up the hill of the driveway, rolled back down, and crashed into the wall and mailbox box. The contact stated that bystanders assisted him up. The bystanders also attempted to open the vehicle; however, the vehicle was still locked. The vehicle was not occupied at the time of the failure. The contact sought medical assistance the next day and was informed that he had sustained separation of muscles on the right side of his back. There was no police report filed. The vehicle was towed to a tow lot, where it was totaled. The dealer was not notified of the failure. The manufacturer was notified of the failure and sent a field inspector to inspect the vehicle. The field inspector informed the contact that the EDR would not indicate the cause of the failure as it could not operate while the vehicle was turned off. The manufacturer later contacted the contact and informed him that they could not assist as the EDR did not reveal the cause of the failure. The failure mileage was approximately 80,000.