The Electronic Frontier Foundation (EFF) has created Rayhunter, a $20 device that helps people detect if police are using fake cell towers to spy on their phones. The device uses a simple traffic-light system — showing a green line when everything is normal, changing to red when it detects potential surveillance.
Police surveillance devices called "Stingrays" mimic real cell towers to trick nearby phones into connecting to them instead of legitimate networks. These fake cell towers can track phones' exact locations, collect unique device identifiers, and potentially intercept communications — all without requiring cooperation from phone companies.
Rayhunter monitors cell tower communications in real-time, alerting users when it spots suspicious activity like attempts to force phones onto less secure networks. When the device detects potential surveillance, it warns users to turn off their phones and saves detailed logs that can be analyzed by security experts.
Unlike previous detection methods that required either modified Android phones or costly radio equipment, Rayhunter works on modern 4G networks using just a simple mobile hotspot. It's designed to be simple enough for anyone to use — from journalists to activists — to help map where and how police are deploying fake cell towers worldwide.
Previously:
• The snitch in your pocket: making sense of Stingrays
• FBI replies to Stingray Freedom of Information request with 5,000 blank pages
• US Marshals raid Florida cops to prevent release of records of 'stingray' surveillance
• Stingray for criminals: spreading mobile malware with fake cellphone towers
