Researchers demonstrate more physical ways to spy on keystrokes

At the CanSecWest security conference this week, researchers Andrea Barisani and Daniele Bianc demonstrated how they were able to determine the letters typed on a laptop some 50 to 100 feet away--with just $80 worth of equipment. This was achieved by pointing a handmade laser microphone on the reflective surface of the keyboard, while a photo diode measures the frequencies from the keystrokes. A technique more often used for speech recognition is then used to guess the letters. While this method necessitates a direct line of sight, it can work through windows.

The duo was able to present a second attack method where they spied on the keystrokes of a desktop computer with a PS/2 keyboard. This was done using a digital oscilloscope and analog-digital converter together with customized filtering to isolate their victim's keystrokes from unrelated noise on the power line.

Barisani explains how this attack is possible: "Information leaks to the electric grid. It can be detected on the power plug, including nearby ones sharing the same electric line as the victim's computer." Fortunately, this attack does not work on laptops--due to their AC/DC converter, as well as data entry via a USB keyboard.

Indeed, these new attack vectors come on the heels of another demonstration last year in which researchers were able to eavesdrop on wired keyboards by monitoring the slight electromagnetic radiation emitted when a key is pressed.

Well, I hope someone will invent a direct neural keyboard interface or something before all these methods get perfected.

For more on this story:
- check out this article at ZDNet

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