We're taking Bluetooth LE hacking from toys and padlocks to the real world. Improving the tools and methods we used in previous research to break the AES cryptography of the NOKE Padlock, we went to do the one thing a mobile hotel key is supposed to prevent: wirelessly sniff someone entering his room - or just unlocking the elevator - and then reconstruct the needed data to open the door with any BTLE enabled PC or even a raspberry pi.
In this talk we will show and explain the tools and methods we used and developed to break the BTLE based mobile phone key system of a large hotel chain. And then come from the academic proof of concept to a reliable setup that can be used in real life scenarios to carry out the attack.
Methods shown will cover the reverse engineering of the wireless protocol based on BTLE captures, analyzing the decompiled mobile phone app and intercepting the TLS encrypted traffic to the back end API, which in combination led to the compromise of the system.