Feeling Bluetooth on the Tooth

Abstract

Bluetooth is a wireless voice and data transmission technology, which can be built into mobile phones, PDAs, USB sticks, keyboards, mices, headsets, printers, telephone facilities in cars, navigation systems, new modern advertisement posters, umbrellas etc. In contrast to infrared, Bluetooth doesn’t rely on direct visual contact to connect to devices. Given good hardware it can even operate through walls and could therefore be compared with Wifi as it’s also radioing on 2.4 GHz frequency. One differentiates between the three device classes 1, 2 and 3, that have different ranges. Class 3 devices radio only up to 1 meter, Class 2 devices can do 10 meter and Class 1 even 100 meter.The design of Bluetooth pays a lot of attention to security. The connection can be encrypted and authenticated. The Bluetooth address is set by the device firmware and not by the operating system kernel, which makes address spoofing harder but not impossible. Despite the attention to security, various vulnerabilities arose in the past in a lot of Bluetooth implementations of vendors like Nokia and Siemens. It now seems to be common for radioing devices to appear in the craziest places; such as keys for houses, garages or car doors.