System and method for preventing malicious can bus attacks

A system for detecting malicious hardware on a data communication network, such as a vehicle CAN bus, is provided. The system includes a teleprocessing device, an AC signal generating device, and an impedance measuring device. In a preliminary step, a set of impedance measurements of N reference AC signals is formed, and a threshold value is set. The signal generating device injects a set of N AC signals into the network bus and the bus impedance for each of the N frequencies is measured, where a set of impedance values of N RT-signals is formed. Then, each of the impedance values of the RT-signals and the impedance values of the respective reference AC signal are statistically compared, to thereby form a set of N comparison-results. Upon determining that any of the impedance values of the RT-signals is greater than the threshold, an alert is activated.