TL*THE CONTACT OWNS A 2008 CADILLAC CTS. WHILE DRIVING 2 MPH WITH THE BRAKE PEDAL DEPRESSED, THE VEHICLE ACCELERATED. THE CONTACT STRUCK THE PRECEDING VEHICLE. THE FRONT BUMPER NEEDS TO BE REPLACED. THE DEALER WAS UNABLE TO DUPLICATE THE FAILURE. THE POWERTRAIN WAS UNKNOWN. THE CURRENT AND FAILURE MILEAGES WERE 1,500.