The contact owns a 2021 Subaru Forester. The contact stated that while the vehicle was parked, she shifted the gear shifter into reverse(R) and the vehicle experienced unintended acceleration and lunged backward, crashing into another vehicle. Additionally, the vehicle made abnormally loud noises and was extremely hot after it was turned off. The contact did not sustain any injuries. No police report was filed. The vehicle was taken to the dealer, and the dealer inspected the brake system. The dealer was unable to duplicate the failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 7,000.