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Compromising Wired Keyboards

Posted by CmdrTaco on from the not-a-lot-of-substance-here dept.

Flavien writes "A team from the Security and Cryptography Laboratory (LASEC) in Lausanne, Switzerland, found 4 different ways to fully or partially recover keystrokes from wired keyboards at a distance up to 20 meters, even through walls. They tested 11 different wired keyboard models bought between 2001 and 2008 (PS/2, USB and laptop). They are all vulnerable to at least one of the 4 attacks. While more information on these attacks will be published soon, a short description with 2 videos is available."

4 of 277 comments (clear)

  1. Time for a Faraday cage? by apathy+maybe · · Score: 5, Interesting

    To determine if wired keyboards generate compromising emanations, we measured the electromagnetic radiations emitted when keys are pressed. To analyze compromising radiations, we generally use a receiver tuned on a specific frequency. However, this method may not be optimal: the signal does not contain the maximal entropy since a significant amount of information is lost.

    Our approach was to acquire the signal directly from the antenna and to work on the whole captured electromagnetic spectrum.

    Looks like a room or building size Faraday Cage (a foil hat the size of your house!) might be the only defence...

    Especially considering that you can also detect what is shown on monitors (again, by detecting the electromagnetic radiation), and so on screen "keyboards" operated with a mouse become not so useful.

    It's not clear from the article whether they have have the keyboard before hand to be able to record which key-press outputs what radiation, or if they can use this (and by that I mean one of the four) technique on any old keyboard, including ones they haven't seen before.

    Anyway, this shouldn't be too surprising to anyone, electronics emit electromagnetic radiation, which can be captured.

    --
    I wank in the shower.
  2. Re:TEMPEST by __aajxax2722 · · Score: 5, Interesting

    I agree. I don't see the big "News Flash" on this. This was well known back in the mid 80's when I fixed computers for the military. They had to be Tempest certified before and after the fixes. It was common knowledge that EMF emissions would be able to be picked up and recorded some distance away from the host computer.

  3. Nothing new by thered2001 · · Score: 5, Interesting

    I saw this demonstrated about 10 years ago while working for a military contractor during a demonstration to increase awareness of security risks. They were able to capture video and keyboard data through a wall adjacent to the PC being monitored. (I can't elaborate on who 'they' were...but I'm sure astute readers can guess correctly.)

    --

    If your only tool is a hammer, every problem becomes a nail.

  4. Shenanigans? by tdc_vga · · Score: 5, Interesting

    If you watch the video he sets the keyboard.eavesdropper into a listening/polling state waiting for keypress information. From there it's filtered and decoded --fine. Now the part that seemed odd to me is it exits as soon as it finds the 'e' in 'trust no one', why?

    If the eavesdropper is in a polling state it should continue looking for more keypresses, unless something there are some smoke and mirrors going on. Also, if you listen there's no termination sent --no keypresses heard on camera.