Dangerous Skills: Understanding and Mitigating Security Risks of Voice-Controlled Third-Party Functions on Virtual Personal Assistant Systems Nan Zhang∗, Xianghang Mi∗, Xuan Fengy∗, XiaoFeng Wang∗, Yuan Tianz and Feng Qian∗ ∗Indiana University, Bloomington Email: fnz3, xmi, xw7,
[email protected] yBeijing Key Laboratory of IOT Information Security Technology, Institute of Information Engineering, CAS, China Email:
[email protected] zUniversity of Virginia Email:
[email protected] Abstract—Virtual personal assistants (VPA) (e.g., Amazon skills by Amazon and actions by Google1) to offer further Alexa and Google Assistant) today mostly rely on the voice helps to the end users, for example, order food, manage bank channel to communicate with their users, which however is accounts and text friends. In the past year, these ecosystems known to be vulnerable, lacking proper authentication (from the user to the VPA). A new authentication challenge, from the VPA are expanding at a breathtaking pace: Amazon claims that service to the user, has emerged with the rapid growth of the VPA already 25,000 skills have been uploaded to its skill market to ecosystem, which allows a third party to publish a function (called support its VPA (including the Alexa service running through skill) for the service and therefore can be exploited to spread Amazon Echo) [1] and Google also has more than one thousand malicious skills to a large audience during their interactions actions available on its market for its Google Home system with smart speakers like Amazon Echo and Google Home. In this paper, we report a study that concludes such remote, large- (powered by Google Assistant).