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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."

7 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.
    1. Re:Time for a Faraday cage? by d3ac0n · · Score: 4, Interesting

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

      This is actually easier to do than you might imagine. My old house was essentially a Faraday Cage. You could NOT get a wireless signal more then 1 foot outside it. Why? Aluminum Siding. Add in aluminum powder tinted windows (triple layer UV and thermal glass) and the only leakage was straight up through the roof.

      So you could get an OK cell-phone signal on the second floor (2 bars), but almost nothing on the first floor. Walk out the front door, 4 bars. Same with WiFi. Full strength "g" signal anywhere inside, walk outside and the connection drops.

      My current home has asbestos siding (bleah!) that does nothing to attenuate the Wifi signal, so I actually had to encrypt my wireless for the first time ever when I moved. I can pick up my wireless signal about 2 doors away now, and it's the same wireless device I used in my old house, located in a roughly similar spot (close to the center of the house, in the basement, on a shelf near the basement rafters)

      If I could I'd re-side in Aluminum again, but the costs to re-side an asbestos tile sided house are astronomical, and many places simply won't do it.

      Regardless, if you really want to attenuate any wireless signals going into or out of your home, slap on some aluminum siding. You'll kill those pesky wireless signals, AND make your house look really nice at the same time.

      --
      Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
  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. Re:TEMPEST by FiveDozenWhales · · Score: 3, Interesting

    Perhaps something like The Optimus Tactus would be ideal?

  5. 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.

  6. Re:TEMPEST by lbgator · · Score: 4, Interesting

    ...I could see a script that generates a random keyboard layout, a key-to-character chart would have to printed on the screen...

    INGdirect does this with their log in. Users have a numeric password, they can enter it by:
    -using the mouse to click the number pad displayed on the screen, or
    -typing the letters that are randomly assigned to the numbers on the screen