Shiver me timbers: Security researchers have demonstrated that it's possible to spy on what's visible on your screen by intercepting electromagnetic radiation from video cables with great accuracy, thanks to artificial intelligence. The team from Uruguay's University of the Republic says their AI-powered cable-tapping method is good enough that these attacks are likely already happening.
Back in the analog video era, it was relatively straightforward for hackers to reconstruct what was on a screen by detecting the leakage from video cables. But once digital protocols like HDMI took over, that became much trickier. The data zipping through HDMI is much more complex than old analog signals.
However, those digital signals still leak some electromagnetic radiation as they transmit between your computer and display. By training an AI model on samples of matching original and intercepted HDMI signals, the researchers were able to decode those leaks into readable screen captures.
Their new technique reconstructed text from pilfered HDMI signals with around 70% accuracy. While that's far from perfect, it's good enough for most human readers to accurately decipher. That potentially means it's easy for hackers to monitor things like password entries, financial data, or encrypted communications.
To test their attack, the researchers used text recognition software on the visuals recovered by their AI model. They could then compare the extracted text to the original screen contents. The team says their method improves the error rate for this type of HDMI cable tapping by a whopping 60% compared to previous techniques.
There are a few ways hackers could pull off this HDMI eavesdropping in the real world. They could plant a discreet signal-capturing device inside the target building. Or just hang out nearby with a radio antenna to grab leaked HDMI radiation as it happens.
The researchers say these attacks are already being used against government agencies and sensitive industrial settings. But these types of organizations likely already shield their facilities against electromagnetic leaks, even if it comes at a significant cost.
However, for the average home or office user, the barrier to entry is still pretty high for this HDMI hacking approach. Deploying the AI models and signal-capturing equipment required isn't trivial.
"Governments are worried about this, [but] I wouldn't say that the normal user should be too concerned. But if you really care about your security, whatever your reasons are, this could be a problem," explains lead researcher Federico Larroca.
There's no need to toss your HDMI cables just yet, but perhaps keep an eye out for shady van operations camped across the street next time you log into your crypto wallets.
AI can see what's on your screen by reading HDMI electromagnetic radiation
