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Sounds or nearby vibrations are just mechanical waves that cause HDD platters to vibrate.
How a Hard Disk Drive Is Designed to Work?
In this case, the hard disk drive must wait until the oscillation stops to perform any operation.
Modern operating systems are equipped with utilities that measure HDD operations.
The accuracy is up to nanosecond.
Ortega realized that these tools could be used to measure delays in HDD operations.
The delay depends on the loudness of the sound.
If the sound is louder, the time of the delay would be longer.
These read write delays enable researchers to reconstruct sound or vibration waves picked up by HDD platter.
Recover Voice May Be Possible
Its not accurate yet to pick up conversations, Ortega said.
However, there is a research that can recover voice data from very low-quality signals using pattern recognition.
I didnt have time to replicate the pattern-recognition portion of that research into mine.
However, its certainly applicable.
Many hard disk specifications are subject to vibration limitation.
This is why they are usually mounted in vibration proof enclosures made of rubber or other isolating materials.
It is easy to infer that HDD can be used to detect sound.
The researcher says that an attacker can use sound waves to launch a resonance attack against an HDD.
In an experiment, he played a 130Hz tone to make an HDD stop responding to commands.
The Linux kernel disconnected it entirely after 120 seconds, Ortega said.
However, with enough energy, any sound will disturb a rotating hard-disk.
