By Johannes B. Ullrich, Ph.D. Ultrasonic Triggers for Cellphone Assistants.
https://source.wustl.edu/2020/02/surfing-attack-hacks-siri-google-with-ultrasonic-waves/
Comparing Information Leakage from Different Browsers
https://www.scss.tcd.ie/Doug.Leith/pubs/browser_privacy.pdf
Cloud Snooper Attack
https://news.sophos.com/en-us/2020/02/25/cloud-snooper-attack-bypasses-firewall-security-measures/
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