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"Decryption" of Bush Memo 55

jjq writes "A decryption of the so-called Bush Memo, see the CNN news, http://edition.cnn.com/2004/ALLPOLITICS/04/10/bush .briefing/ was presented at Eurocrypt 2004 (Interlaken) during the rump session. David Naccache shown how to recover words from removed text in several memos. See more about this story at Lemonde.fr (sorry, it is written in French)." Just use the the fish.
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"Decryption" of Bush Memo

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  • by krymsin01 ( 700838 ) on Saturday May 08, 2004 @06:43AM (#9092536) Homepage Journal


    Cryptologists decipher a term censured in a "memo" addressed by the CIA to Geoges Bush
    THE WORLD|07.05.04| 12h58 UPDATED 07.05.04|16h13
    Les annales et corrig÷Ydu baccalaurïE depuis 1995.
    Abonnez-vous au Monde.fr, 5? par mois

    A passage covered with black ink in a document recently diffused by the White House was reconstituted. The method could be applied to considerable d¦classifi¦es files.
    It "was bored" in front of television, the weekend of Easter, "when the memo of the CIA with George Bush was diffused" , remembers David Naccache, specialist in the coding of the data of the French company Gemplus. "I telephoned at once Claire Whelan, a coed of Dublin City University, from which I direct the thesis, to propose to him to attack the caviard¦s passages" , it tells. Mission accomplished, or almost.

    The "memo" in question, addressed on August 6, 2001 by the CIA to president Bush and entitled "Ben Laden determined to strike in the USA", had been just d¦classifi¦ by the White House. This one wanted to prove that the precision of the warnings of the services of information was not sufficient to make it possible to the president to prevent the attacks of September 11. But five passages specifying the sources of the collected information had been covered with black ink.

    For the cryptologist David Naccache, these illegible fragments were as many red rags. The result of its efforts - "conduits on a purely deprived basis" , specifies it, concerned not to imply its employer in his initiative - was presented Tuesday May 4 at the time of the conference Eurocrypt 2004 which joined together until May 6 with Interlaken, in Switzerland, the gratin of world cryptography. "the demonstration was extremely impressive" , judge Jean-Jacques Quisquater (university of Leuwen-the-New), specialist in the field, which greets this company of " reverse engineering of censured document" .

    David Naccache and his pupil indeed succeeded in discovering one of the censured words. The term "Egyptian" seems the only possible one to them. They want to polish their method before returning their verdict on a longer passage, in order not to discredit it. And they straightforwardly threw sponge for a completely isolated word, for lack of sufficient indices.

    Technology employed does not have, at first sight, anything revolutionist. The two researchers initially "rectified" the text, deformed at the time of its digitalization - the slope was only of 0,52ã. They then used a software of character recognition to determine the police force of the text which fixes the number of signs per unit of length. The simple recourse to an English dictionary then makes it possible to draw up a list of possible words. "1 530 corresponded" , indicates David Naccache.

    But the article "year" preceding the word mystery implied that this one necessarily started with a vowel, which made it possible to bring back the list to 346 words. In French, an index provided by articles like "one" or "one", in the same way, would have made it possible to tighten research. The selection was also facilitated by the fact that the bill of character, Arial, is "proportional", i.e. the "hunting" of the letters varies. The space occupied by an I differs from that taken by W, which can give additional indices, compared to the police forces known as "monospace", like the Mail, often used, where all the letters are worth.

    "Among" the surviving "words, five or six could make direction, but only Egyptian corresponded to the context" , indicates the cryptologist. This last stage raises more human intelligence than of the geometry of the text. To choose among Ukrainian, univited, unofficial, incursive, Egyptian, indebted and Ugandan, the two researchers were based on their good direction, Uganda and the Ukraine seeming too far away from the theatre of the operations to be retained, for example.

    No doubt the analysis of the "memo" of the CIA reveals only one "an open secre
    • But the article "year" preceding the word mystery implied that this one necessarily started with a vowel,


      Google translates Mais l'article "an" as 'But the article "year" ' it this case an means an not year.

      I guess translating mixed languages is a bit harder .
    • The result of its efforts - "conduits on a purely deprived basis"

      A self-referential comment by the translation software?
    • conduits on a purely deprived basis?
      throwing sponge?
      "monospace" police force?

      Sounds like a conspiracy to me!
    • by Peter Desnoyers ( 11115 ) on Sunday May 09, 2004 @10:24PM (#9103567) Homepage
      Here's a cleaned up version of the translation. My French isn't great, but it's better than the fish. (although it's great having a computer do the grunt work...)

      A passage covered with black ink in a document recently release by the White House was reconstituted. The method could be applied to a considerable number of declassified files.

      He "was bored" in front of television, the weekend of Easter, "when the memo from the CIA to George Bush was released" , remembers David Naccache, a cryptographer at the French company Gemplus. "I immediately telephoned Claire Whelan, a student at Dublin City University, whose thesis I supervise, to propose to her to attack the blacked-out passages" , he relates. Mission accomplished, or almost.

      The memo in question, sent on August 6, 2001 by the CIA to President Bush and titled "Bin Laden determined to strike in US", had just been declassified by the White House, which wanted to prove that the accuracy of warnings from intelligence services had not been sufficient to allow the president to prevent the attacks of September 11. But five passages specifying the sources of the collected information had been covered with black ink.

      For the cryptologist David Naccache, these illegible fragments were red flags. The result of his efforts - "conducted on a purely private basis" , he specifies, concerned not to implicate his employer in his initiative - was presented Tuesday May 4 at the Eurocrypt 2004 conference, which met until May 6 in Interlaken, Switzerland, the gratin (???) of world cryptography. "The demonstration was extremely impressive" , judged Jean-Jacques Quisquater (University of Louvain-la-Neuve), specialist in the field, who applauds this technique of "reverse engineering censored documents".

      David Naccache and his student indeed succeeded in discovering one of the censured words. The term "Egyptian" seems the only possible one to them. They want to fine-tune their method before rendering a verdict on a longer passage, in order not to discredit(???) it. And they totally threw in the sponge on a completely isolated word, for lack of sufficient indices.

      The technology employed is not, at first glance, revolutionary. The two researchers initially straightened the text, deformed at the time of its digitalization - the slope was only 0.52 degrees. They then used character recognition software to determine the point size of the text which determines the number of characters per unit length. A simple recourse to an English dictionary then makes it possible to draw up a list of possible words. "1,530 matched" , indicates David Naccache.

      But the article "an" preceding the mystery word, implied that this one necessarily started with a vowel, which made it possible to reduce the list to 346 words. In French, an index provided by articles like "un" or "une", in the same way, would have made it possible to tighten the search. The selection was also aided by the fact that the character font, Arial, is "proportional", i.e. the width of the letters varies. The space occupied by an I differs from that taken by W, which can give additional indices, compared to the fonts known as "monospace", like Courier, often used, where all the letters are the same width.

      "Among the remaining words, five or six could fit, but only Egyptian corresponded to the context" , indicates the cryptologist. This last stage relies more on human intelligence than the geometry of the text. To choose among "Ukrainian", "uninvited", "unofficial", "incursive", "Egyptian", "indebted" and "Ugandan", the two researchers used their common sense. Uganda and the Ukraine seemed too far away from the theatre of the operations to be retained, for example.

      No doubt the analysis of the CIA memo of the CIA reveals only an open secret, recognizes David Naccache. But the method automates the research. (???) In another memo, it revealed that civil helicopters militarized by the Iraqis had been bought in South Korea. And nothing prevents the automated application of this technique to an group of declassified documents, which might one day allow it to uncover "isolated words, or even groups of two or three words".

    • Now, if only we can get these guys to decipher this article.
  • by Anonymous Coward
    Babelfish link [altavista.com]
  • Altavista's babelfish is babelfish.altavista.com [altavista.com] not .net as provided in the post.

    Not that I was able to decipher much of it anyway even with the fish.

  • by Anonymous Coward on Saturday May 08, 2004 @08:09AM (#9092802)
    Unprecendented secrecy in the present U.S. administration. You are not allowed to know what your government is doing.

    He lied. They died.
  • The technique (Score:5, Informative)

    by Anonymous Coward on Saturday May 08, 2004 @09:43AM (#9093416)
    The memo was written ina proportional font. It's a standard MS Windows font, so he can easily find the exact width of each letter (and kern pairs and the like). By looking at surrounding words, and allowing for the justification stretch on the line, you can figure out the exact width of the blacked-out words.

    Then it's just a matter of doing a dictionary search to find which words could possibly fit, and use context information to figure out which one of the possibles it is.
    • That seems pretty obvious.

      I actually wanted to make a "Font Scanner" once that would take an image of text and the actual text and compare it with all the fonts on a system to find the closest match.

    • Re:The technique (Score:5, Informative)

      by belmolis ( 702863 ) <billposer@alu m . m i t.edu> on Saturday May 08, 2004 @10:41AM (#9093755) Homepage

      To fill in a detail, they made use of the fact that the blacked out word is preceded by "an", from which they deduced that it had to begin with a vowel. The Babelfish mistranslation of this as "year" is therefore particularly misleading.

      • That's not a mistranslation. "An" is the French word for "year"..
        • I know that an means "year" in French. But in context it is a mistake because it isn't the French word for year, it is a quoted English word.

          • But how is Babelfish (or whatever translation software) supposed to deal with it?
            • I wasn't saying that Babelfish is particularly bad as translation software goes, merely that the mistranslation was particularly unfortunate in this case because the word "an" was key to decipherment. The use of a word from another language is of course a particularly difficult thing for translation software to deal with. The fact that it is quoted is a hint that it might be something that shouldnt be translated but by no means a certain indicator. This is probably an example of translation that cannot be

  • Why read a description when you can have a PDF of the August 6, 2001 PDB. [cnn.com]
  • Now... (Score:2, Funny)

    by daishin ( 753851 )
    If only someone was able to "decrypt" everything Bush says.
    • As an American, everytime that man gets on televison and opens his mouth, I just shake my head in disbelief. One would think, that after 3.5 years as president he could have gained <i>some</i> public speaking skills and/or a basic grasp of the English language.
      <p>
      What really frightens me is when I look at GWB, I have to ask myself, "Of all the great people we have in this country, the best we could do is this???"
      <p>
      I look at Kerry and Bush and I throw my hands up in disgust. They'r
  • Some months ago, the US State Department announced [msn.com] that it would change it's departmental typeface from Courier 12 to Times Roman 14. According to sources within the department, the new typeface takes up almost exactly the same area on the page as Courier New 12, while offering a crisper, cleaner, more modern look.".

    The Central Intelligence Agency may have instituted similar changes prior to August 2001 for similar reasons. Had they continued to use the fixed-width Courier, instead of the prettier Arial,

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