Fake mobile phone towers sucking in data across US

4 Sep 2014

Across the US, a number of illegal devices that pose as mobile phone towers to harvest data are spreading but a German company has found a way to locate them.

The practice of erecting these devices as a means of gathering people’s locations, messages and other personal information has seen them designated ‘IMSI catchers’, an acronym of the term ‘International mobile subscriber identity’, according to Wired.

Compared with regular mobile phone towers, these devices are much more portable as they are usually turned on while in a moving vehicle, such as a van. They also appear to provide a much stronger signal to mobile phones, meaning their connection will be favoured automatically over a weaker signal.

While the device does not actually act as a functioning broadcaster of mobile phone signal, it does make sure the targeted phones remain unaware they are being intercepted as the IMSI catchers tether the phone onto the nearest legitimate tower.

Few ways to track them

The American Federal Communications Commission (FCC) has attempted to combat the growing number of bogus signals, albeit ones that are being run by hackers and potential foreign intelligence agencies, not those of the US government.

Currently, there appears to be only one phone that can properly trace and protect against one of these rogue signals, the GSMK Cryptophone 500 produced in Germany, which uses an expensive and altered Samsung Galaxy S3 with Android software, priced at about US$3,000.

The phone uses a detection system that can quite accurately find the location by finding the device’s or tower’s ID.

However, the software used by the German company is yet to be offered to the wider commercial market, meaning many of the IMSI devices will remain operating for the time being.

Mobile phone towers image via Shutterstock

Colm Gorey was a senior journalist with Silicon Republic