You don’t need to read the payment data. I think a phishing/spoofing attempt may be possible by playing a louder or directional ultrasonic message to introduce an alternate payment url. Or you may be able to accomplish a denial of service via jamming.
(If some one knows more, please step in and comment.) I’m guessing some of these could be issues with NFC too but from what I have skimmed online it seems both the tag and receiver would need to be modified to work at larger than normal distances of “1-5cm”[1]. Also much more power is needed to extend the range of NFC than sound since sound strength diminishes with the square of the distance and, from what I have skimmed, magnetic induction used by nearfield NFC diminishes with the cube of the distance [2][3].
1: https://seritag.com/learn/using-nfc/nfc-tag-scan-distance-ex...
2: https://www.physicsforums.com/threads/magnetic-field-strengt...
3: https://physics.stackexchange.com/questions/44037/why-is-nea...
Re:Ultrasonic Payments
by heretogetout on Tuesday June 07, 2022 @11:44PM
(#31662954)
Like an audio QR code, I guess.
Seems like an interesting way to start a transaction without needing to buy any specialized equipment.