The method has been dubbed "DiskFiltration" by its creators because it uses acoustic signals emitted from the hard drive of the air-gapped computer being targeted. It works by manipulating the movements of the hard drive's actuator, which is the mechanical arm that accesses specific parts of a disk platter so heads attached to the actuator can read or write data.By using so-called seek operations that move the actuator in very specific ways, it can generate sounds that transfer passwords, cryptographic keys, and other sensitive data stored on the computer to a nearby microphone. The technique has a range of six feet and a speed of 180 bits per minute, fast enough to steal a 4,096-bit key in about 25 minutes. more
Solution: Upgrade to a solid state drive.