Maritime Border Security Review Act (Sec. 3) This bill directs the Department of Homeland Security (DHS) to submit to Congress a maritime border (i.e., the transit zone and the borders and territorial waters of Puerto Rico and the U.S. Virgin Islands) threat analysis that includes an identification and description of: current and potential terrorism and criminal threats posed by individuals and groups seeking to enter the United States through the maritime border or exploit border vulnerabilities on the maritime border; improvements needed at U.S. seaports to prevent terrorists and instruments of terror from entering the United States and reduce criminal activity, as measured by the total flow of illegal goods and illicit drugs, related to the maritime border; improvements needed with respect to the maritime border to prevent terrorists and instruments of terror from entering the United States and reduce criminal activity related to the maritime border; vulnerabilities in law, policy, cooperation between state, territorial, and local law enforcement, or international agreements that hinder effective and efficient border security, counterterrorism, anti-human trafficking efforts, and the flow of legitimate trade relating to the maritime border; and metrics and performance parameters used by DHS to evaluate maritime security effectiveness. In preparing the threat analysis, DHS shall consider and examine: technology and personnel needs and challenges; the role of state, territorial, and local law enforcement in general border security activities; the need for cooperation among federal, state, territorial, local, and appropriate international law enforcement entities relating to border security; the geographic challenges of the maritime border; and the impact and consequences of Hurricanes Harvey, Irma, Maria, and Nate on general border security activities relating to the maritime border.