Monitoring personal devices (smartphones, tablets, PCs) and using them is a serious threat to privacy as it allows potential malicious people to monitor the activities of each of us and obtain information that They can then be used in a less ethical or, worse, fraudulent way. Particularly insidious and worrying is that monitoring that happens invisibly and without the user’s being aware of it. In this case, it is a real invasive spy action that can also reveal sensitive data such as Sexual orientation, health status, or religious beliefs. Clearly, there are those who have every interest in taking our data and treasuring them for their own purposes, and that is why control tools are created that use more and more sophisticated methods. A new technique for invading the personal sphere of users and analyzing them, without knowing them, behaving, tracing habits and interests, is the one that involves the use of ultrasonic messages.
It might seem simple science fiction, but today this possibility is real: technology has been developed by a number of advertising and marketing companies and is called “ultrasound cross-device tracking” or “uXDT”. This technique uses sounds not directly perceived by our senses, because they are high frequency, but at the same time perfectly able to interact with our personal devices. These ultrasounds can be sent via loudspeakers in stores, or inserted into TV or radio spots, or even hidden in the JavaScript code of advertisements posted on the Internet. Although, as said, they can not be captured by the human ear, instead they are intercepted and collected by the microphones of our smartphones, tablets or PCs. Then, the applications on them, if they have been authorized to access the microphone, receive ultrasound signals, interpret and connect with specific remote servers by sending location, interest, and any other information that may serve To create targeted promotional offers. In practice, using this ad-tracking technology allows ad companies to link consumer habits to a user’s identity by creating a personalized database of tastes, choices, and habits to access to send messages based on them . For example, you might get into a store that sells jewelery, or animal supplies, or sportswear, and from that moment on, receive advertising messages related to the items in that store; Or you might watch an action movie on TV, and receive all the clips about new action movies out there; Or it might happen to visit a site that sells cars on the PC, and to receive, from that moment on, on their cellphone or tablet the advertising of new cars. But not only. Anyone who has access to the personalized database of tastes, choices, and habits could link an individual in a precise way to observing sensitive content such as adult movies or political or religious documents, and then use it more than please. The alert on this technique comes from Germany, where a group of researchers from Brunswick Technical University has discovered 234 Android applications that include the ability to listen to ultrasound “without the user being aware of it.” Many of these applications have been downloaded thousands or millions of times, and the list includes different types of software, such as games, news apps, or more. Researchers also found traces of ultrasonic transmissions even in the broadcasting sound system of the stores of four major European chains and in their Android smartphone apps. But how do I find apps that include such control features? In fact, there is no simple and direct method, at least not for ordinary users. However, it is important to remember that in order to exploit uXDT, the app must have access to the microphone, and that permission is explicitly required during the installation phase (although it is usually allotted without too much trouble). Therefore, any application that makes such a request can potentially represent a “trojan horse” to enable ultrasonic tracking. So, if there is no reason why an app, like a game or news application, should have access to your microphone, the wisest thing is not to grant it.
Giovanni Calcerano