The CDT (Center for Democracy & Technology) has warned the FTC (Federal Trade Commission) of releasing ads that have high-frequency embedded sounds and violate users' privacy.
According to the formal complaint (PDF) filed by CDT, advertisers such as SilverPush, Drawbridge, and Flurry develop and hold advertisements that load high-frequency sounds on the devices that appear.
CDT reports that these ultrasound sounds scan the space for other devices, such as mobile phones, tablets, televisions, computers, and wearables, linking their presence with a browser cookie, an IP address, and indirectly with the user.
Each time the device owner opens a page serving these ads, the ad network is able to identify them based on “fingerprints αποτυπώματα” της συσκευής που υπάρχουν καταγεγραμμένα στις βάσεις data their. In the data collected there are of course also the traces of previous visits from other devices that have been marked by the ultrasound sounds.
Η technology is quite dubious as it allows advertisers to track users even if they don't want to be tracked. Furthermore, the practice does not include options that users could use to protect themselves.
Η CDΤ αναφέρει ότι από τον Απρίλιο του 2015, διαφημίσεις με υπερήχους και το λογισμικό εντοπισμού της SilverPush (SDK), έχει ενσωματωθεί σε 67 εφαρμογές για κινητά, επιτρέποντας στην εταιρεία να παρακολουθεί 18 εκατομμύρια smartphones and an unknown number of nearby devices.
The FTC is reviewing the CDT's complaint, and is expected to make an official announcement in the coming days.
