Some companies and government agencies

Some companies and government agencies will ensure that confidential computers are completely isolated from the outside world and that the Internet is not connected. But now someone has found a way to get the data out.

Researchers at the University of Ben Gurion in Israel recently found a new way to steal data using noise, DiskFiltration.Cpu Holder Manufacturers

It works by infecting a computer isolated from the Internet with malware that can generate specific audio by controlling the motion of the drive arm on the hard disk.

The confidential digital information in the computer is transmitted to nearby receivers such as smartphones or computers through these specific sound signals. After receiving the noise information, the program converts it into binary information of 0 and 1.

Using this method, they can also steal networked computers protected by a tight security system.

The technology currently has a working range of only 6 feet, a transmission rate of 180 bits per minute, and the ability to steal 4096-bit keys in 25 minutes.

Mordechai Guri, head of the university's Cyber Security Lab, said that although the air gap-isolated computer is completely isolated from the Internet, it is not without flaws. With DiskFiltration they can transfer confidential data from one computer to a nearby mobile phone.

There are a lot of similar technologies at the moment, and researchers at the lab have developed a method of acquiring data from such computers using computer cooling and built-in thermal sensors last year, BitWhisper.

However, these technologies also have very large limitations. For example, if a computer is replaced with a non-mechanical SSD, hackers cannot use DiskFiltration to steal data.

In addition, whether using noise or using thermal sensors to transmit data, the target computer must be infected with malware.

This is very difficult for a computer that completely isolates the Internet, but it is not impossible. Earlier reports said that there were intelligence agencies in the restaurant near the Pentagon deliberately "drop" the U disk, expecting US military staff to insert into the work computer during the meal.