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