Used by various US agencies for years now, Stingrays allow their operators to snoop on cell phone calls and messages. They aren’t legal, so it is interesting that Homeland Security is admitting they exist – seemingly because “bad actors” are now using them as well.
So basically, if any corporation or government might have a strong desire to intercept your calls, don’t use your phone.
Via Wired:
The DHS statement came in the form of a response to senator Ron Wyden, who had inquired about rogue cell-site simulators in a November letter. DHS acting undersecretary Christopher Krebs wrote, “Use of IMSI catchers by malicious actors to track and monitor cellular users is unlawful and threatens the security of communications, resulting in safety, economic, and privacy risks. … Overall, [DHS’s National Protection and Programs Directorate] believes the malicious use of IMSI catchers is a real and growing risk.” The agency added that NPPD “has observed anomalous activity in the Nation Capital Region that appears to be consistent with IMSI catchers. NPPD has not validated or attributed such activity to specific entities or devices.”