Department of Defense Civilian Cybersecurity Reserve Act This bill requires the Department of the Army to establish a Civilian Cybersecurity Reserve via a four-year pilot project to address malicious cyber activity and cyber workforce challenges. Under the pilot project, the Department of the Army may appoint up to 50 members to the Civilian Cybersecurity Reserve at any time. Such appointees must be considered to be federal civil service employees. Individuals who are employees of the executive branch may not be recruited or appointed to serve in the Civilian Cybersecurity Reserve. The Department of the Army must issue guidance establishing and implementing the pilot project.