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- IMSI catchers, or “Stingrays,” pretend to be cell towers in order to gather data on nearby phones.
- So far, it’s been very difficult to know if you’ve been a victim of IMSI-catcher monitoring.
- The EFF’s new Rayhunter project uses a hacked mobile hotspot to attempt to detect IMSI catchers.
Privacy advocates will often be quick to tell you: Even with the best smartphones, you’re pretty much volunteering to carry around a surveillance device. And depending on the laws where you live, it might not take much at all for law enforcement to convince a court to let them use those surveillance tools against you. But not all attempts by law enforcement to gather information from phones involve anything as explicit as eavesdropping, nor necessarily require a court’s sign-off. Now, the Electronic Frontier Foundation (EFF) is sharing a new tool for fighting back against one of those surveillance techniques.
We’re talking about IMSI (International Mobile Subscriber Identity) catchers, which you may have heard referred to by the brand name Stingray. Basically, this is hardware that pretends to be a cellular tower. Police (or whatever agency wants to use them) can set up IMSI catchers and then watch as unsuspecting phones nearby attempt to connect. Install that at something like a political protest, and you’ve got an instant list of potential targets.
