GoKawiilAliExpress Caught Using Inaudible Audio Signals to Fingerprint Site Visitors
Researcher Matthew Callaghan discovered AliExpress running hidden scripts that generate silent, inaudible sound waves through the WebAudio API to create a unique fingerprint of each visitor's browser. He noticed the tracking only because it interfered with his multipoint Bluetooth headphones, cutting off phone audio whenever the AliExpress tab was open. The scripts muted the sound with a zero gain setting so users would never notice, but the browser still processed and transmitted the audio data back to the site.