Cut It: Deauthentication Attack on Bluetooth

Abstract

Bluetooth is a short-range wireless communication technology that is widely used nowadays. It has been deployed in millions of devices including laptops, watches, mobile phones, cars, printers, and many other smart devices. Although Bluetooth provides some security mechanisms, the technology is still subject to various types of attacks. In this paper, we present a security vulnerability that we have discovered on many Bluetooth devices. This vulnerability can be exploited to generate a deauthentication attack on paired Bluetooth devices causing their disconnection. In contrary to many other Bluetooth attacks that require certain skills and budget for their generation, the attack that we present in this paper does only require ordinary skills, cheap hardware, and free software. The security vulnerability is due to an implementation flaw in the way existing Bluetooth connections are handled, rather than a flaw in the Bluetooth specification (IEEE 802.15.1). We demonstrate through various attack patterns how the vulnerability can be exploited to cause deauthentication and disconnection of Bluetooth devices. Also, we discuss and recommend possible options to address the vulnerability.