A user commuting to work via public transport received an offensive image on their smart phone
from another commuter. Which of the following attacks MOST likely took place?

A.
War chalking

B.
Bluejacking

C.
War driving

D.
Bluesnarfing

Explanation:
The question states that the ‘attack’ took place on public transport and was received on a
smartphone. Therefore, it is most likely that the image was sent using Bluetooth.
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 metres (32.8 ft) on mobile phones, but
laptops can reach up to 100 metres (328 ft) with powerful (Class 1) transmitters.
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.