Wireless home automation systems are becoming increasingly popular. They can help users save energy and increase the comfort.However, this increased convenience also comes with new attack vectors. Many available systems provide little to no security. In this paper, we explore the possibilities of passive attacks against these systems. We exemplarily investigate two real-world installations of off-the-shelf home automation systems to see what amount of information can be obtained by a passive adversary.Our results show that the systems provide no privacy. They leak information about the users' habits as well as their presence and can be abused to plan burglaries. Furthermore, we conclude that even encrypted communication does not fully protect against the attack presented here. In particular, it is still possible to predict user presence and absence even if individual actions cannot be identified.
7th ACM Conference on Security and Privacy in Wireless and Mobile Networks (ACM WiSec 2014)