Built-in antennas make it possible to install electromagnetic fingerprints on the gutters of computer equipment. This is enough to detect even minor physical intrusions.
To hack computers, some high-flying hackers do not hesitate to get their hands dirty and attach cookies directly to the motherboard or input-output interfaces. This is what the example is for NSA On routers that were in traffic, as revealed by Edward Snowden. We also remember the rumors Back doors Chinese products It is integrated into super micro servers.
If we can verify the hardware integrity of an equipment, we can thwart this type of attack. There are already solutions at the component or SoC level. “Usually it is a kind of plastic film with thin threads, covered with hardware components. If the image is damaged, the system will trigger an alarm ”Paul Stott, a researcher at Ruhr-Bochum University and the Max Blanc Institute, explains in an article.
With his colleague Johannes Tobisch, he has developed a technique that allows you to control the integrity of an entire system, for example the server. The idea is to rely on electromagnetic waves.
In fact, two researchers took a motherboard and inserted two antennas into it, one transmitting and the other receiving (in pink in the photo above). Then they put everything in a perforated Faraday cage. Before coming to the receiver, the emitted electromagnetic signal is slightly modified due to the presence of various electronic components on the motherboard. This modification is very unique, allowing you to establish the actual track of the device.
Not only that. To see how this affected the wave propagation, the researchers inserted a series of needles through holes in the Faraday cage. Surprise: The change in the electromagnetic fingerprint of the motherboard is noticeable enough to detect space intrusion. This is even when the motherboard is fully functional. Under optimal conditions, the researchers were able to detect the introduction of a 16 mm needle with a thickness of 0.1 mm. “The closer the needle is to the receiving antenna, the easier it is to detect. In practice, it is important to think carefully about where the antennas should be placed. They should be as close as possible to components that are particularly safe.Researchers say.
This technology is already being used by some cyber security companies to protect vital infrastructure. But a precursor, nothing prevents widespread use, even by the general public.