Bluesnarfing
Bluesnarfing is the unauthorized access of information from a wireless device through a Bluetooth connection, often between phones, desktops, laptops, and PDAs. This allows access to a calendar, contact list, emails and text messages, and on some phone users can copy pictures and private videos. Both Bluesnarfing and Bluejacking exploit others' Bluetooth connections without their knowledge. While Bluejacking is essentially harmless as it only transmits data to the target device, Bluesnarfing is the theft of information from the target device.
Current mobile software generally must allow a connection using a temporary state initiated by the user in order to be 'paired' with another device to copy content. There seem to have been, in the past, available reports of phones being Bluesnarfed without pairing being explicitly allowed. After the release of this vulnerability vendors of mobile phone patched their Bluetooth implementations and, at the time of writing, no current phone models are vulnerable to this attack.
Any device with its Bluetooth connection turned on and set to "discoverable" (able to be found by other Bluetooth devices in range) may be susceptible to Bluejacking, and possibly to Bluesnarfing if there is a vulnerability in the vendor's software. By turning off this feature, the potential victim can be safer from the possibility of being Bluesnarfed; although a device that is set to "hidden" may be Bluesnarfable by guessing the device's MAC address via a brute force attack. As with all brute force attacks, the main obstacle to this approach is the sheer number of possible MAC addresses. Bluetooth uses a 48-bit unique MAC Address, of which the first 24 bits are common to a manufacturer . The remaining 24 bits have approximately 16.8 million possible combinations, requiring an average of 8.4 million attempts to guess by brute force.
Because Bluesnarfing is an invasion of privacy, it is illegal in many countries.