Mexico. A group of researchers showed how it is possible to recreate the image of a monitor through the interception of electromagnetic radiation from video cables, a potential form of espionage and theft of information. ESET, a leading company in proactive threat detection, analyzes the phenomenon and tells how to keep information protected.
A group of security professionals demonstrated that it is possible to spy on the screen of a user using an HDMI cable and obtain information about what they are observing in real time. For example, personal credentials. What this team verified is that, thanks to Artificial Intelligence, it is possible to know what is being seen on the screen due to the interception of electromagnetic radiation from video cables.
"The authors were able to reconstruct text from intercepted HDMI signals, with close to 70% accuracy. The potential is enormous: whether to monitor password entries, financial data or other information," says Camilo Gutiérrez Amaya, Head of the Research Lab at ESET Latin America.
The term TEMPEST (Transient ElectroMagnetic Pulse Emanation STandard) refers to the problem of clandestine eavesdropping on digital video screens for which the analysis of electromagnetic waves that involuntarily emanate from cables and connectors, particularly HDMI, is used.
Stealing wireless electromagnetic signals for surveillance purposes as such is not a new idea. In fact, its origins date back to the espionage that was carried out in the Second World War. Of course, until today it was not thought that HDMI cables were susceptible to it.
In this scenario, there are many paths open for cybercriminals, who manage to see their victims' screens wirelessly through HDMI radiation: from locating a signal capture device inside the target building or staying nearby with a radio antenna to capture the filtered HDMI radiation at the time it occurs.
The Uruguayan research team that identified the finding claims that these attacks are already happening against government agencies and sensitive critical industries, according to Techspot. Although they assure that it is very likely that these organizations are already protected against this type of electromagnetic leaks.
How to protect yourself in this scenario?
There are various protection measures to prevent monitor spying via HDMI. On the one hand, they advise the technique of cable "shielding", that is, using the sheathing or shielding of the cables so that this can influence a lower SNR (Signal-to-Noise Ratio) in reception.
"In addition, the use of two wires together or more, as bundling or "tying" such wires together can create destructive interference between them, resulting in an unintentional overlap of both signals. Although the probability of an espionage attack being carried out using this technique is low due to its complexity, research of this type shows that when talking about technology, security risks can be in the least expected places. In addition, as an important point, it is always advisable to consider security from the design stages, since, just as this team of researchers discovered how to extract information that travels through an HDMI cable, there can always be someone with bad intentions looking for a way to test the security of a certain technology," adds Gutiérrez Amaya from ESET.
