A hard drive stores data. From a layman’s point of view, that is the main function of a hard drive. It stores our precious digital data.

Apparently, the function of a hard drive can get more interesting than that. In the future, a hard drive can do more than just that.

Eggheads at the University of Michigan in the US, and Zhejiang University in China, have found that hard disk drives (HDDs) can be turned into listening devices, using malicious firmware and signal processing calculations.

(Via: https://www.theregister.co.uk/2019/03/07/hard_drive_eavesdropping/)

So, if you think that only walls have ears; think again. Here’s how two computer scientists are making it possible for hard drives to eavesdrop.

For a study titled “Hard Drive of Hearing: Disks that Eavesdrop with a Synthesized Microphone,” computer scientists Andrew Kwong, Wenyuan Xu, and Kevin Fu describe an acoustic side-channel that can be accessed by measuring how sound waves make hard disk parts vibrate.

“Our research demonstrates that the mechanical components in magnetic hard disk drives behave as microphones with sufficient precision to extract and parse human speech,” their paper, obtained by The Register ahead of its formal publication, stated. “These unintentional microphones sense speech with high enough fidelity for the Shazam service to recognize a song recorded through the hard drive.”

(Via: https://www.theregister.co.uk/2019/03/07/hard_drive_eavesdropping/)

Although their research was presented in May this year, it’s something that we should all look forward to.

The team’s research work, scheduled to be presented in May at the 2019 IEEE Symposium on Security and Privacy, explores how it’s possible to alter HDD firmware to measure the offset of a disk drive’s read/write head from the center of the track it’s seeking.

The offset is referred to as the Positional Error Signal (PES) and hard drives monitor this signal to keep the read/write head in the optimal position for reading and writing data. PES measurements must be very fine because drive heads can only be off by a few nanometers before data errors arise. The sensitivity of the gear, however, means human speech is sufficient to move the needle, so to speak.

“These extremely precise measurements are sensitive to vibrations caused by the slightest fluctuations in air pressure, such as those induced by human vocalizations,” the paper explained.

Vibrations from HDD parts don’t yield particularly good sound, but with digital filtering techniques, human speech can be discerned, given the right conditions.

(Via: https://www.theregister.co.uk/2019/03/07/hard_drive_eavesdropping/)

Now, wait a minute. As interesting as it may sound, it’s sounds alarming as well. If hard drives could discern and eventually store human speech, then it could possibly pick up more than just a wealth of information.

Aside from the data that we aim to store in it, bits and pieces of information that come out of our mouth could be stored as well. When that happens, we could end up documenting a lot of things, even things that we have no intention of documenting. Bottom line is, that is scary. Hard drives turning into microphones are scary.

It’s hard to get into the technical part of the research. But from a layman’s point of view, there is a possibility that hard drives could eventually capture and store spoken language.

In this age of technology, nothing is impossible. The time will come when the function of a hard drive is going to level up. Its capacity to store data is going to be limitless in due time.

Before we get to the moment when hard drives can capture and store human speech, it’s important to remember that hard drives fail as well. No matter how limitless their functions are, they can fail as well.

That’s the reason why we should take data recovery seriously. When we deal with hard drives, we not only deal with data storage but with hard drive recovery as well. If we care enough to know what a hard drive can do in the future, we should care enough to know how to recover files from it as well.