Author: Eric Voskuil 2015-02-05 23:22:50
Published on: 2015-02-05T23:22:50+00:00
The email thread discusses the security issues with the use of Bluetooth Low Energy (BLE) technology for bitcoin transactions. The main concern is that all attacks (DOS, privacy, integrity) in this scenario can be fully-automated and executed over the air by a black box at some distance. For instance, DOS is possible by rebroadcasting a similar request, while privacy is compromised by monitoring for payment requests and correlating them to location and potentially images of parties. Integrity is compromised by rebroadcasting a similar transaction with a bogus address but with the same leading characters or by rebroadcasting with a valid address that doesn't match the leading characters, in the expectation that the user doesn't check manually. Although BIP-70 signed payment request in the initial broadcast can resolve the integrity issues, it makes the privacy compromise much worse due to the public nature of the broadcast coupled with strong public identity. Therefore, the initial broadcast needs privacy, but then it cannot be a broadcast - it needs to be a narrow cast. This brings us back to proximity-based establishment. BLE has an advertised range of over 100m, which could be extended dramatically by the reviewer in case of mass surveillance. However, Bluetooth isn't going to be enabling mass surveillance any time soon because it barely goes through air, let alone walls.
Updated on: 2023-06-09T16:29:40.950615+00:00