DHS Overseas Personnel Enhancement Act of 2017 (Sec. 2) This bill directs the Department of Homeland Security (DHS), by 90 days after the submission of the 3-year strategy for DHS international programs required under the National Defense Authorization Act for Fiscal Year 2017 and every 180 days thereafter, to brief the congressional homeland security committees on DHS personnel with primary duties that take place outside of the United States. The briefing shall include: a detailed summary of each type of personnel position with such duties and how each such position contributes to DHS's counterterrorism mission, information related to how the geographic and regional placement of such positions contributes to such mission, information related to the position-specific training received by such personnel before and during placement at a foreign location, challenges that may impede the communication of counterterrorism information between DHS personnel at foreign locations and DHS entities in the United States, the status of efforts to implement the three-year strategy for DHS international programs, and the status of efforts to implement a plan to enhance the effectiveness of DHS personnel at foreign locations. (Sec. 3) DHS shall submit to the congressional homeland security committees a plan to enhance the effectiveness of DHS personnel at foreign locations, which shall include proposals to: improve efforts of DHS personnel for purposes of providing foreign partner capacity development and furthering DHS's counterterrorism mission; redeploy DHS personnel to respond to changing threats to the United States; enhance collaboration among DHS personnel at foreign locations, other federal personnel at foreign locations, and foreign partners; improve the communication of counterterrorism information between DHS personnel at foreign locations and DHS entities in the United States; and maintain practices to guard against counter-espionage threats associated with DHS personnel. (Sec. 4) The briefing requirement shall terminate four years after the submission of the three-year strategy for DHS international programs.