A first look into Alexa's interaction security

With a rapidly increasing market of millions of devices, the intelligent virtual assistants (IVA) have become a new vector available to exploit security breaches. In this work we approach the third revision of the Amazon Echo ecosystem's device Alexa from a security perspective, focusing our efforts on the interaction between the user and the device. We found the client-server communications to be robust using encryption, but studying the voice message recognition system we discovered a method to execute voice commands remotely, a feature not available by default. This method could be used against the user if an attacker manages to perform a session hijacking attack on the web or mobile clients.