Bluetooth Pairing Vulnerabilities & Suggestive Measures

Abstract

The most widely and cheap mode of transmission over short distances is by using Bluetooth device. Bluetooth is most common mode to transmission between mobile phones. To make data secure for both sides of transmission, it uses key exchange algorithm named Elliptic Curve Diffie-Hellman algorithm for short term and long term key development. During the design phase of Bluetooth device, its security was not focused, hence it was vulnerable from hacker’s point of view. In the era where information is the most powerful tool, any eavesdropping may lead to the bigger threat. Bluetooth devices lack key feature authentication and is thus vulnerable to Main in the Middle (MITM) attacks. In this dissertation, we analyzed the vulnerability present in Bluetooth v 4.0 and above from both exploitation and encounter methods. The new variant of invalid curve attack that preserve only x-coordinate of public keys is recently presented, this new attack is successful against all present Bluetooth paring devices protocols. Thus both of the pairing devices are vulnerable to this attack. This thesis also includes the suggestive measures against this vulnerability that can be considered as key exchange features for the development of upcoming Bluetooth v 5.0.