Mechanical hard drive sounds can be used to steal passwords, documents and other data

Mechanical hard drives now have another disadvantage over solid-state disks as researchers discovered a way to steal data through the noise that the parts make when accessing data.

While most of the world is worried about hackers stealing data through their apps and emails, researchers from the Ben-Gurion University of the Negev in Israel have found a way to siphon off data without the need for an Internet connection at all.

One of the most obvious tips to be safe from hackers is to disconnect entirely from the Internet. Without a channel for the hackers to communicate with their malware, they would not be able to issue commands or to steal data. The process is called air-gapping and it is commonly used in high-security places such as government data archives and such.

Researchers have now found another method to steal data off of air-gapped systems through DiskFiltration using just the sounds of the mechanical hard drive's spinning disks, PC World has learned. The sound can just be recorded using an ordinary smartphone that can also be placed on a desk near the system for covert stealing of data.

One disadvantage is that a malware needs to make its way to the system first. The purpose of the malware is to use the mechanical hard drive's arm to make sounds whenever the disks spin which can be translated to the stolen data.

Another disadvantage is the slow rate of the file transfer through the hard drive's sound. The DiskFiltration method can only send out the files at an excruciatingly slow speed of 180 bits per minute, ExtremeTech reported.

At that rate, stealing just 200KB will take 148 hours or nearly a week's time. However, the method could still be used to steal encryption keys or bits of sensitive code as they can just be sized around one to two kilobits.

Of course, the obvious move for such air-gapped systems is to just use SSDs instead of mechanical hard drives for air-gapped systems as the former does not make any noise at all. Seagate just unveiled the world's first 60TB SSD which is designed for data centers and they are even planning to jump up to 100TB.