Security researcher Chris Paget revealed the insecurity of 2G GSM calls by demonstrating how you can intercept these calls with just $1,500 worth of equipment, with the most expensive item being a laptop. His system works by creating a cell phone base station that tricks cell phones into routing their outbound calls through his device, encryption is irrelevant as the rogue tower can simply turn it off.
The low-cost, home-brewed device, developed by researcher Chris Paget, mimics more expensive devices already used by intelligence and law enforcement agencies – called IMSI catchers – that can capture phone ID data and content. The devices essentially spoof a legitimate GSM tower and entice cell phones to send them data by emitting a signal that’s stronger than legitimate towers in the area.
“If you have the ability to deliver a reasonably strong signal, then those around are owned,” Paget said.
Paget’s system costs only about $1,500, as opposed to several hundreds of thousands for professional products. Most of the price is for the laptop he used to operate the system.