US captures phone data with fake cellphone towers on planes

The Wall Street Journal wrote yesterday that the US Marshals Service (USMS) is using small, fixed-wing Cessna planes to capture cell phone data from fugitives and criminals. The data is captured with so-called dirtboxes, receivers that act like cellphone towers, but one of the side effects is that these planes capture data from tens of thousands of cell phones on the ground. Non-target phone data is reportedly let go as it is gathered but the secret gathering of phone details from every citizen without their knowledge has civil liberties experts concerned.

The Cessna flights reportedly take place on a regular basis but usually target multiple suspects at a time to keep costs down. Full details at ARS Technica.

Sources told the WSJ that USMS operated these planes from five major airports in the US and that the program had a flying range “covering most of the US population.” The devices on the planes can capture unique identifying information from “tens of thousands” of cellphones on the ground. Using that information, federal authorities can pinpoint a cellphone user's location from “within three meters or within a specific room in a building,” the WSJ said.

Individuals with knowledge of the matter told the news outlet that the plane flyovers were targeted at “fugitives and criminals” and that non-target phone data is “let go” as it is gathered. The dirtboxes are described as higher-grade Stingrays, which police use on the ground to collect International Mobile Subscriber Numbers (IMSI).