The contact owns a 2019 Hyundai Tucson. The contact stated while driving at approximately 40 MPH and slowing the vehicle, she observed that the vehicle in front was braking. The contact depressed the brake pedal and the pedal went to the floorboard as she was depressing it. The contact stated that she was pumping the brake pedal and she stated that the vehicle jerked and crashed into the rear end of the vehicle in front of her. No warning light was illuminated. The contact stated that her front end was damaged by the trailer hitch ball on the other vehicle. The contact stated that the hood was dented and the grill was broken, also there was damage to her headlights, and both lights were cracked. The damage to the other vehicle was minimal, only scratches. The contact's vehicle had to be towed. The contact stated she and the other driver were not injured. The police were on the scene and filed a report. The vehicle was towed to a collision center and was repaired. The manufacturer was informed of the failure. The failure mileage was approximately 38,000.