Bluejacking is the sending of unsolicited messages over Bluetooth to Bluetooth-enabled devices such as mobile phones, PDAs or laptop computers, sending a vCard which typically contains a message in the name field (i.e. for bluedating or bluechat) to another bluetooth enabled device via the OBEX protocol.
Bluetooth has a very limited range, usually around 10 meters on mobile phones, but laptops can reach up to 100 meters with powerful (Class 1) transmitters.
Origins
'Bluejacking' was reportedly first carried out by a Malaysian IT consultant who used his phone to advertise Sony Ericsson. He also invented the name, an amalgam of Bluetooth and 'ajack', his username on Esato, a Sony Ericsson fan online forum.
Usage
Bluejacking is usually harmless, but because bluejacked people generally don't know what has happened, they may think that their phone is malfunctioning. Usually, a bluejacker will only send a text message, but with modern phones it's possible to send images or sounds as well. Bluejacking has been used in guerrilla marketing campaigns to promote advergames.
With the increase in the availability of Bluetooth enabled devices, these devices have become vulnerable to virus attacks and even complete take over of devices through a trojan horse program.
Bluejacking is also confused with Bluesnarfing which is the way in which mobile phones are illegally hacked via Bluetooth.
