TEDW. LIEU 
33RD DISTRICT, CALIFORNIA 
COMMITTEE ON THE BUDGET 
COMMITTEE ON OVERSIGHT 
AND GOVERNMENT REFORM 
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August 22, 2016 
The Honorable Tom Wheeler 
Chairman 
Federal Communications Commission 
445 Twelfth Street, SW 
Washington, DC 20554 
Dear Chairman Wheeler, 
415 CANNON HOUSE OFFICE BUILDING 
WASHINGTON, DC 20515 
(202) 225-3976 
5055 WILSHIRE BOULEVARD, SUITE 310 
Los ANGELES, CA 90036 
(310) 652-3095 
1600 ROSECRANS AVENUE, 4TH FLOOR 
MANHATTAN BEACH, CA 90266 
(310) 321-7664 
Thank you for opening an investigation on April 20 into the Signaling System Number 7 (SS7) 
flaw. This defect allows foreign governments, criminal syndicates and sophisticated hackers--if 
they simply know a cell phone number--to acquire voice communications and text messages 
from the target cell phone. In light of the recent cyber hack at the DCCC that released cell phone 
numbers of all Democratic Members of Congress--reportedly conducted by the Russian 
Government--our foreign adversaries can now acquire cell phone voice and text data of over 180 
Congress members with impunity. This problem is particularly acute given reports that Russia is 
trying to influence elections in America. 
I write to request that the Federal Communications Commission (FCC) expedite its investigation 
of the SS7 flaw and for the FCC to give an estimate of when the investigation will be completed. 
I also write to request the FCC provide me and other affected Members of Congress with what it 
has learned so far about the SS7 flaw so that we can respond appropriately to the recent hack. 
The SS7 problem is no longer a theoretical threat. We now have a mass release of cell phone 
numbers of Members of Congress likely caused by a Russian government that has full access to 
utilize the SS7 flaw. Because we don't know how long the hackers had access to this 
information, it is very possible nearly half of Congress has already had voice and text data 
intercepted. Other enemy adversaries, such as North Korea and Iran, could also take this 
information and acquire the cell phone voice and text data of multiple Members of Congress. 
The ramifications of the SS7 flaw can be severe, both for our national security and the integrity 
of American elections. 
Thank you for your attention to this critical matter. 
Sincerely, 
Ted W. Lieu 
Member of Congress 
Cc: Hon. Nancy Pelosi 
Hon. Ben Ray Lujan 
Mike Dabbs 
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