Smart Phone and Next Generation Mobile Computing

Mobile Security and Privacy 383

6.4.2 Bluetooth Weakness and Attacks

The use of a PIN code during pairing presents some security risks [9].

The length of a PIN can be between 8 and 128 bits. It could come

with the device or can be selected by the user. Prior to link key

exchange, an initialization key will first be computed, which in

turn uses the PIN code. An attacker may make an exhaustive search

over all possible PINs up to a specific length. To verify its guess,

the attacker only needs to eavesdrop on the communication chan-

nel between two victims to capture random numbers in cleartext

and perform the initialization key algorithm. When the PIN code

is obtained, the attacker can compute the initialization key and

the link key. Eventually, the encryption ...