Firstly lets understand these two terminologies...
a.)Bluejacking: It is method of the sending of unsolicited messages over Bluetooth to Bluetooth-enabled devices such as mobile phones, PDAs or laptop computers. This is not serious as the vitim only gets a message on his phome.
b.)Bluesnarfing: It is a methond of getting unauthorized access of information from a wireless device through a Bluetooth connection, often between phones, desktops, laptops, and PDAs. Is much more serious in relation to Bluejacking.
This allows access to a calendar, contact list, emails and text messages and even make calls.
Here is a video demonstrating how somebody can use your open Bluetooth connection to access your mobile and make calls also for free.
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