from the snitching-on-snitches dept.
IMSI catchers, otherwise known as stingrays, are those surveillance tools that masquerade as cell towers and trick mobile phones into connecting, spewing private data in the process. Law-enforcement agencies have been using them for almost two decades, but there's never been a good way for individuals to detect them. Now Lily Hay Newman reports that SnoopSnitch scans for radio signals that indicate a transition to a stingray from a legitimate cell tower. "SnoopSnitch collects and analyzes mobile radio data to make you aware of your mobile network security and to warn you about threats like fake base stations (IMSI catchers), user tracking and over-the-air updates." say German security researchers Alex Senier, Karsten Nohl, and Tobias Engel, creators of the app which is available now only for Andriod. The app can't protect people's phones from connecting to stingrays in the first place, but it can at least let them know that there is surveillance happening in a given area. "There's no one set of information, taken by itself, that allows you to detect an IMSI catcher," says Nohl. "But we do stream analysis of everything that happens on your phone, and can come out with a warning if it crosses a certain threshold."
Stingrays have garnered attention since a 2011 Arizona court case in which one agent admitted in an affidavit that the tool collaterally swept up data on “innocent, non-target devices” (U.S. v. Rigmaiden). The government eventually conceded in this case that the “tracking operation was a Fourth Amendment search and seizure,” meaning it required a warrant. But given that the Justice Department has continued to claim that cellphone users have no reasonable expectation of privacy over their location data, it may take a Supreme Court judgement to settle the Stingray issue countrywide.