A more TLDR article about this: https://www.extremetech.com/defense/173108-researchers-crack-the-worlds-toughest-encryption-by-listening-to-the-tiny-sounds-made-by-your-computers-cpu
FAQs from the researchers: https://web.archive.org/web/20230130225254/http://www.cs.tau.ac.il/~tromer/acoustic/
I don’t know that much about audio sidechannels so I don’t know how realistic this would be, but my immediate thought is whether this can be extended to extract not just a single key but other data as well. For example, if you had a phone next to a computer that was reading and displaying a text file that contained confidential information, or perhaps reading values from a database, could it be possible to leak the actual data this way?
I also wonder how many videos and audio recordings made near computers have encryption keys and other sensitive data hidden in them, just waiting to be decoded. Or whether a video recorded by a smartphone can reveal what the phone is doing in the background. A terrifying prospect.
It only works on chosen cyphertexts. They don’t specify is that means “any file, but the attacker has to get access to it” or if it means “this very specific file that we made in order to do this attack”.
The former being much more dangerous than the latter of course.
According to the FAQ:
Which sounds to me like the latter?
but, you surely will agree, this is pretty devastating for any target. known cleartext may be trivial to insert into a targets workflow, and the confirmed recovery of a private key is potentially a massive payoff.
the ability to process and extract sensitive information from the local environment has gotten seriously scary.