Transnational Criminal Organization Exploitation Threat Assessment Act This bill directs the Department of Homeland Security (DHS), through the Under Secretary for Intelligence and Analysis, to conduct a threat assessment of the exploitation by transnational criminal organizations of the unaccompanied alien children services program. Upon completion of the assessment: (1) DHS shall direct component agencies, including U.S. Customs and Border Protection and U.S. Immigration and Customs Enforcement, to address identified security vulnerabilities; and (2) the Under Secretary shall disseminate such assessment to federal, state, and local partners.