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Amazon.com Hosting Crypto-Contest

vic20 pointed us over to Amazon's crypto contest/promotional item. Crack the message, and you can get signed editions of books like Cryptonomicon, Applied Cryptography, The Code Book, and Between Silk and Cyanide as well as LEGO Mindstorms. They'll be giving more hints as the contest goes on, with a deadline of 11:59 PM PST Oct. 29.

7 of 184 comments (clear)

  1. Signed Copies of Cryptonomicon on Ebay. by jelwell · · Score: 3

    For those who don't like random drawing/contest - you can bid for Signed copies of Cryptonomicon... Signed by Neal Stephenson or even Linus Torvalds.

    -Note: I'm not selling either. :)
    Joseph Elwell.

  2. SOLUTION-Oh, Amazon, feel the mighty effect of /. by Nylathotep · · Score: 3

    Or at least I believe its the solution.

    As someone pointed out, the first 4 groupings is the ISBN of the book. If you pull up the book in Amazon, each has a review by Amazon. The numbers are word offsets. The key thing to figure out is what they consider a word... I just did a preliminary scan through and came up with the following, if someone spends some time, they can undoubtably get it right...

    Resonates from 918 tech to Alan

    all ties brilliant coffers an sinks in

    sent explains department cut and to men forget zoo would than

    People need the bestselling conflict in the Information Age

    The suitable specialist offers steps for secure source


    As you can see, its not perfect. I was using Word, cutting text then using word count to get position. Things like hypenated words were screwing me up. But the last two sentences seem to well fitted to be chance.

    if your asking why im posting this, well, this is some scam contest they are running for two weeks, with a "random drawing" at the end. Yeah right. Ive spent about as much time as I want to on it, Id be curious to the final solution once whoever it is puzzles it...

  3. distributed.net would not crack this! And a HINT by Section9 · · Score: 3
    Distribuited.net's approach to brute-force cracking works fine, so long as you know how the message was encrypted, but just neet to find the proper key to decrypt it.

    What Amazon has done is to give people the cypher-text and challenged them to recover the plain-text.

    This is why crytanalysis is SOOO interesting. This is more of a "real-world" scenario. You get some stuff and have to find out how it was encrypted and what it says.

    Amazon's challenge is much more difficult than the RSA challenges. RSA tells you what encryption algorythm is used and what the beginning of the plain-text message is.... all that's left is key-recovery. Here people will have to think about how to attack the problem first, then try breaking the code.

    HINT: Presuming that Amazon's message is in English, and is most likely a cypher (be it block, substitution, output feedback) with standard math knowedge necessary, I can offer the following assumptions for all the budding crypoanalysts on /. ::

    It is most likely a subtitution cypher

    It is somewhat likely that these are not added modulus anything. (Due to the high range of values)

    A good starting point would be to compare the recurring numbers within the cyphertext with common letters in the English language.

    Most of all: Have fun...At least you don't do this for $$

  4. I got it! by Signal+11 · · Score: 4

    The message is "this message is not yet here."

    --

  5. More notes by Kaa · · Score: 4

    As has been pointed out, 0380973464 is the ISDN for Cryptonomicon, so

    038-097-34-64-242-335-51-377-183-168
    ---ISDN------ C R Y P T O

    038-097-34-64-380-330-115-289-273-189-56
    ---ISDN------ N O M I C O N

    and further on,

    068-486-42-23-87-434-10-468-151-345-150-494-376- 415-426
    ---ISDN------ T H E C O D E B O O K





    Kaa

    --

    Kaa
    Kaa's Law: In any sufficiently large group of people most are idiots.
  6. Re:SOLUTION [CONTAINS SPOILERS] by Seth+Finkelstein · · Score: 4
    The lines seem to relate to the books themselves

    038-097-34-64-242-335-51-377-183-168
    Cryptonomicon
    This is a truly strange deception
    038-097-34-64-380-330-115-289-273-189-56
    Cryptonomicon
    funky protagonists are destined to want appendices
    068-486-42-23-87-434-10-468-151-345-150-494-376-41 5-426
    Between Silk and Cyanide : A Codemaker's War 1941-1945
    He had great marks for the easiest execution of enemy explosions
    038-549-53-15-1-193-121-29-109-66-28-160-106
    The Code Book : The Evolution of Secrecy from Mary, Queen of Scots to Quantum Cryptography
    People need the bestselling conflict in the information age
    047-111-70-99-24-21-25-12-53-22-56-8
    Applied Cryptography : Protocols, Algorithms, and Source Code in C
    The suitable specialist offers steps for secure source

  7. Time and some strategy by Shaheen · · Score: 5

    Well, not that I'm a crypto expert, but let's see how quickly a brute force decipher could take...

    Okay, I obviously have to make a few assumptions. First off, I assume each number between dashes is a single alphanumeric. And since I said alphanumeric, you know I mean A-Z and 0-9.

    There are 61 alphanumerics in this message. HOWEVER, I believe we can safely assume that each line is a phrase on its own. If so, we can solve each separately. The breakdown is 10, 11, 15, 13, and 12 (yes, that adds to 61).

    So, we have 36^n combinations for each line (n being the # of alphanumerics in each line).

    Sum(36^n for all n) = approx(2.1249 * 10^23)

    Let's say that it takes 1 millisecond to calculate a single permutation. (I have *no* idea whether that is a fair estimate - I'm definitely no expert in cryptography).

    This would make worst case time for solving the code would be 7.011 * 10^12 years. Of course, this doesn't rule out the possibility that there are multiple valid solutions (ie. the code interpreted differently still results in a valid English statement) and other such weird phenomena. I would guess the best chance to cracking this thing, at first, would be to find the weights of each of the numbers between the dashes, and compare that to the English alphabet's weight. At least, that might get you an E or something. I'll let someone who knows what he's talking about comment on that.

    --
    You should never take life too seriously - You'll never get out of it alive.