Guarding against Unauthorized Attacks Related to Driving Act or the GUARD Act This bill requires the Department of Transportation (DOT) to study the state of cybersecurity regarding motor vehicles, including by developing a comprehensive list of federal agencies with jurisdiction over cybersecurity and a brief description of the jurisdiction or expertise of such agencies. DOT must also report on the results of the study and make recommendations to enable the exchange of information and lessons learned across the industry, and across relevant federal agencies, regarding cybersecurity incidents, threats, and potential vulnerabilities in a timely manner with respect to motor vehicle safety.