There are already hackers out there who have unleashed destructive malware that can erase files from your hard drive. Now security researchers have shown that your files can be damaged by sound.
A hard drive is a miraculous thing, capable of storing hundreds of thousands of files in a tiny amount of space. The components inside a hard drive that make the magic happen are packed together very tightly. That leaves little room for error when things are spinning at several thousand RPMS and floating just a few nanometers apart.
Hard drives really, really don’t like to be bumped. That’s why manufacturers started building in anti-shock systems many years ago. It’s difficult for those systems to defend against vibrations caused by sound, however.
A team of U.S. and Chinese researchers has demonstrated an attack that uses ultrasound and audible sound to cause a drive to malfunction. Blasting a drive with the right frequencies at the right volume can interrupt normal reading and writing tasks. It can even cause physical damage to the disk.
Interestingly enough, the team was able to hijack a laptop’s speakers and use them to disrupt its own drive. They did it by simply auto-playing an audio file embedded on a website. In other tests, they placed sound emitters near a computer. In both cases, the operating systems (Windows and Ubuntu Linux) reported errors and eventually froze up or crashed when attacked.
It doesn’t take all that long for the attack to make an impact, either. As little as 45 seconds is enough.
It’s also possible, the researchers say, that these acoustic attacks could be executed from a distance. Long Range Acoustic Devices such as the ones used by police for crowd control could potentially produce sounds that would do the job.
This kind of attack could be tricky to defend against. New drives could be re-engineered to better dampen outside sounds, but that wouldn’t do anything for existing drives. Foam can help, but it would also trap in heat — and excessive heat will also wreak havoc on a hard drive.