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Hidden Codes in Printers Cracked

Posted by CmdrTaco on from the big-brother-pwnz-you dept.

r84x writes "A research team led by the Electronic Frontier Foundation (EFF) recently broke the code behind tiny tracking dots that some color laser printers secretly hide in every document. The U.S. Secret Service admitted that the tracking information is part of a deal struck with selected color laser printer manufacturers, ostensibly to identify counterfeiters. However, the nature of the private information encoded in each document was not previously known. "We've found that the dots from at least one line of printers encode the date and time your document was printed, as well as the serial number of the printer," said EFF Staff Technologist Seth David Schoen."

18 of 562 comments (clear)

  1. Maybe its not a weakness by suso · · Score: 5, Funny

    Its a good thing that I can't print. [warning: experimental music made from printer noises]

    1. Re:Maybe its not a weakness by suso · · Score: 4, Funny

      There is a fine line between Offtopic and Funny.

    2. Re:Maybe its not a weakness by suso · · Score: 3, Funny

      What the? Now damnit, why was that marked as funny. Mark my grandparent post as funny.

    3. Re:Maybe its not a weakness by mwood · · Score: 3, Funny

      Interesting, yes, but too old to be funny. Many moons ago somebody made a program that could play tunes by fiddling with the timing of the hammers on an IBM 1403 line printer. It's good to see someone keeping the traditions alive. :-)

  2. Printer Friendly Version? by OctoberSky · · Score: 5, Funny

    Anyone have a printer friendly version? On second thought.... nevermind. //Tin foil hat on

    1. Re:Printer Friendly Version? by Smidge204 · · Score: 4, Funny

      Forget the tinfoil hats! Everything I print from now on will be on foil-backed paper!

      =Smidge=

    2. Re:Printer Friendly Version? by LiquidCoooled · · Score: 3, Funny

      Print everything with pretty yellow floral background and all will be fine :D

      --
      liqbase :: faster than paper
    3. Re:Printer Friendly Version? by LearnToSpell · · Score: 5, Funny

      Not if they search your house when you're not home! No inconvenience for anyone! In fact, you might not even know they've been there. Everybody wins.

      --
      Haida Manga
    4. Re:Printer Friendly Version? by Basehart · · Score: 3, Funny

      "All you need is to scan anything that they have printed and copy the hidden code on the page and then use image software to overlay that code onto your own page image and print it using a printer that doesn't embed its own code"

      Create multiple layers in photoshop, each with its own secret code. Be sure to title each layer with a name so you don't send Nancy down when it was Joe who looked at you funny that morning last week.

  3. Message decoded by GroeFaZ · · Score: 4, Funny

    "If you can read this, you are about to be busted"

    --
    The grass is always greener on the other side of the light cone.
  4. Date and time? by Anonymous Coward · · Score: 5, Funny

    I bet most people's printers will print "Jan-01 1980 12:00" in little blinking dots.

  5. Re:Before... by sisina · · Score: 4, Funny

    Holy crap! 600,000 people are watching every move I make? Where's my Xanax??

  6. Blue light scanner mod ? by Animaether · · Score: 4, Funny

    You'd think it would be easier to...

    A1. scan as normal
    A2. separate the channels into CMYK in Photoshop/whathaveyou
    A3. inspect the Yellow channel.

    B1. scan as normal
    B2. separate the channels into RGB in GIMP/whathaveyou
    B3. do a difference matte between the channels
    B4. inspect the result

    C1. replace the yellow toner cartridge with a black one
    C2a. stock the other holders with empty cartridges
    C2b. or if that causes a printer error/warning, block the cartridges' output
    C3. print

    D1. get a sheet of blue filter plastic
    D2. scan through that

    But I guess the array of blue LEDs with soldering involved is a lot more geeky :)

  7. pacman to the rescue by Junior+J.+Junior+III · · Score: 4, Funny

    Just send in the little round yellow guy to eat some of the dots and confuse the feds. No more paranoia!

    --
    You see? You see? Your stupid minds! Stupid! Stupid!
  8. Re:more links by meringuoid · · Score: 4, Funny
    Also interesting is Andrew Bunnie's flat bed page scanner mod to use blue light instead of white. This made the yellow tracking dots easier to see, and the whole page could be seen at once to determine the pattern they made.

    Right. So now, in order to ensure that we remain safe from terrorists, paedophiles, and liberals, we need to compel scanner manufacturers to make sure their products will refuse to show the secret codes we already compelled the printer manufacturers to install.

    Don't worry, citizen. We have it all under control.

    --
    Real Daleks don't climb stairs - they level the building.
  9. Re:Old Communist ploy gets updated by $RANDOMLUSER · · Score: 3, Funny

    I didn't say you were paranoid, you must have imagined that.

    --
    No folly is more costly than the folly of intolerant idealism. - Winston Churchill
  10. Re:Watermark with extra random patterns by Mccavity91k · · Score: 5, Funny

    "What's this? This ransom note was printed in 1455 on printer number 1! Okay men, I think we need to have a little chat with Mr. Gutenberg"

  11. Re:So they "cracked" it... by Pusene · · Score: 3, Funny

    This would be fun:

    1. Mail local politician and ask for something, get nice letter in reply.
    2. Decode info hidden in letter.
    3. Create Communist, Satanist and other anti-government propaganda with fake, hidden info.
    4.???
    5. Profit!

    --
    Error #13: No coffee. Operator halted. Please place boot device at bottom.