METHOD FOR HANDLING CASE OF DETECTING UNAUTHORIZED FRAME TRANSMITTED OVER ONBOARD NETWORK

An anomaly handling method using a device installed outside of a vehicle is disclosed. The method includes receiving, from the vehicle, an anomaly detection notification, which includes level information indicating a level affecting safety, and a location of the vehicle. The method also includes obtaining a location of another vehicle and determining whether a distance between the location of the vehicle and the location of the other vehicle is within a predetermined range. When the distance is within the predetermined range and is shorter than a first predetermined distance, not changing the level information and transmitting the received anomaly detection information to the other vehicle. When the distance is within the predetermined range and is longer than or equal to the first predetermined distance, changing to decrement a level indicated by the level information, and transmitting changed anomaly detection information to the other vehicle.