(This measure has not been amended since it was reported to the House on May 16, 2017. The summary of that version is repeated here.) Border Enforcement Security Task Force Reauthorization Act of 2017 (Sec. 2) This bill amends the Homeland Security Act of 2002 to require the Department of Homeland Security (DHS), before establishing a Border Enforcement Security Task Force (BEST) unit, to apply risk-based criteria that takes into consideration specified factors, including: whether the area in which the unit would be established is significantly impacted by threats posed by transnational criminal organizations; the extent to which the unit would advance DHS's homeland and border security strategic priorities and related objectives; and whether departmental Joint Task Force operations would be enhanced, improved, or otherwise assisted by the unit. A BEST unit with a port security nexus must be composed of at least one member of each of: (1) the Coast Guard Investigative Service, and (2) the geographically-responsible Coast Guard Sector Intelligence Office. The bill requires DHS to submit an annual report on the BEST program for the next five years, and such report must include: a description of the effectiveness of BEST in disrupting and dismantling transnational criminal organizations; an assessment of how BEST enhances information-sharing, including the dissemination of homeland security information, among federal, state, local, tribal, and foreign law enforcement agencies; a description of how BEST advances DHS's homeland and border security strategic priorities and effectiveness of BEST in achieving related objectives; and an assessment of BEST's joint operational efforts with departmental Joint Task Force operations.