Action at a Distance
Now that you have a basic understanding of how Bluetooth works, let’s talk about the threats against Bluetooth devices. The first thing to remember about Bluetooth is that it’s a wireless technology. It may seem a silly thing to think about, but there is a tendency to minimize the wireless aspect of Bluetooth, because its general operating range is usually only a few meters for normal devices. However, an attacker using an antenna can access a device from much further away. For instance, a phone probably has a 1–10 milliwatt radio in it and is accessed by other devices in the same room. But an attacker with a $50 antenna will be able to access that phone from at least 100 meters away...just as far as a normal WiFi connection.
Since the frequency range for Bluetooth is the same as for many WiFi devices, the WiFi antennas on the market can be used to boost Bluetooth signals. This makes hacking hardware for long-distance Bluetooth access even easier, because WiFi antennas are available all over the country, in places like CompUSA. The ease of acquisition of these antennas and the distance at which a device can be accessed means that any vulnerability in a device can be accessed from a distance, giving attackers a much lower risk of being physically caught. This is the same situation that WiFi is experiencing, and it’s best to treat Bluetooth and WiFi in the same manner with respect to their radio frequency characteristics.