A survey on Bluetooth Low Energy security and privacy
Since its introduction in 2009, Bluetooth Low Energy (BLE) has become a remarkable success. Due to its unique properties of low power requirements and its ubiquitous availability in practically every smartphone, it outnumbered classic Bluetooth BR/EDR in most areas. It enabled a multitude of new product categories like smart watches or connected health care devices that would not be feasible without such a technology. We are currently facing version 5.2 of the specification which is the result of a number of major and minor revisions, each fixing problems of earlier versions while adding new features and capabilities. This includes more secure pairing methods, like secure connection pairing. Cyber security was considered from the beginning of the Bluetooth specification and has been improved with each specification release. On the other hand, security weaknesses in the specification as well as in individual Bluetooth stack implementations have been identified. Designing a secure BLE device, or analyzing its security is a complicated task due to the overwhelming number of possible configurations. As the specification introduces constantly new features and subtle changes regarding privacy and security, this will become an even more complex task. To the best of our knowledge, no systematic overview over the current state of BLE does exist that covers the security and privacy properties of the different BLE versions and features including known weaknesses and attacks in a single place. With this survey we want to fill this gap.