RON WYDEN COMMITTEES OREGON COMMITTEE ON FINANCE COMMITTEE ON BUDGET COMMITTEE ON ENERGY NATURAL RESOURCES RANKING MEMFITVRANCSOMMWEE ON tEd ta t g Kngt SELECT COMMITTEE ON INTELLIGENCE WASHINGTON DC 20510 3703 JOINT TAXATION 221 DIRKSEN SENATE OFFICE BUILDING WASHINGTON DC 20510 202 224 5244 November 17 2017 Christopher Krebs Senior Of cial Performing the Duties of the Under Secretary National Protection and Program Directorate Department of Homeland Security Washington DC 20528 Dear Mr Krebs I write seeking information about foreign intelligence services using fake cell phone towers in the United States I am very concerned by this threat and urge the Department of Homeland Security DHS to improve its efforts to detect such activity Fake cell towers often known as catchers or stingrays impersonate cell phone towers to locate and identify nearby phones and to intercept calls and text messages covertly IMSI catchers are widely available from surveillance vendors around the world and can be constructed using open source software In 2014 security researchers reported that they detected a number of IMSI catchers in the National Capital Region which they suggested may have been operated by foreign governments The Federal Communications Commission FCC subsequently established a task force to investigate the threat posed by foreign governments and criminals using IMSI catcher technology Unfortunately the FCC has yet to issue any public ndings or guidance since then Whether foreign intelligence services and criminals are using IMSI catchers to spy on senior members of the US government is undoubtedly a question worth answering Foreign government surveillance of senior American political and business leaders would obviously pose a signi cant threat to our country s national and economic security mandate includes the security and resilience of America s cyber and communications infrastructure Given this role I am seeking information about awareness of the threat posed by IMSI catchers and the steps DHS has taken to respond appropriately To that end please respond to the following questions 0 Has DHS seen any evidence of foreign IMSI catchers operated in the National Capital Region 0 If yes was this evidence reported to any congressional committees 0 Does DHS agree that foreign government use of IMSI catchers in the National Capital Region poses a threat to US national and economic security 911 NE 11TH AVENUE 405 EAST 8TH AVE SAC ANNEX BUILDING US COURTHOUSE THE JAMISON BUILDING 707 13TH ST SE SUITE 630 SUITE 2020 105 FIR ST 310 WEST 6TH ST 131 NW HAWTHORNE AVE SUITE 285 PORTLAND OR 97232 EUGENE OR 97401 SUITE 201 ROOM 118 SUITE 107 SALEM OR 97301 503 326 7525 541 431 0229 LA GRANDE OR 97850 MEDFORD OR 97501 BEND OR 97701 503 589 4555 541 962 7691 541 858 5122 541 33079142 PRINTED ON RECYCLED PAPER Does DHS currently have the technical capability to detect foreign IMSI catchers in the National Capital Region 0 If yes has DHS deployed assets capable of detecting foreign IMSI catchers in the National Capital Region 0 If no what would DHS need to have this technical capability Has DHS seen evidence of foreign IMSI catchers in other major US cities and does DHS agree that foreign IMSI catchers in other cities would pose a serious threat to US national and economic security 0 If DHS has seen evidence of foreign IMSI catchers in other major US cities what steps has DHS taken to respond Native 4th Generation IMSI catchers are now openly advertised by surveillance technology companies Does DHS currently have the technical capability to detect IMSI catchers If not what resources if any has DHS invested to address this advanced surveillance threat I appreciate your attention to this important matter If you have any questions please contact Chris Soghoian on my staff at 202 224 5244 Sincerely Ron Wyden United States Senator This document is from the holdings of The National Security Archive Suite 701 Gelman Library The George Washington University 2130 H Street NW Washington D C 20037 Phone 202 994-7000 Fax 202 994-7005 nsarchiv@gwu edu