Vehicle immobilization is a security function that prevents a car from starting or from being driven. It may disable the ignition, fuel, starter, or another control path so the vehicle cannot move until the restriction is cleared. In legitimate systems, it is used for theft prevention, fleet control, or remote recovery.
In cyber security, immobilization matters because it turns a digital command into a physical effect. If an attacker can abuse Bluetooth, a mobile app, a telematics service, or a poorly protected control module, they may be able to stop a vehicle or deny its use without touching the car. Defenses include strong authentication, secure pairing, signed firmware, access controls, and careful limits on which commands can affect safety-critical functions.