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Domain: md5crk.com

Stories and comments across the archive that link to md5crk.com.

Comments · 9

  1. Re:Self Defeating by hunterx11 · · Score: 1 · on Detecting Faked Photographs Gets Easier

    They are already trying to find MD5 collisions.

  2. Re:Um, no by __aafkqj3628 · · Score: 1 · on Online MD5 Cracking Service

    Theoretically, they can't... but given the size of an md5 hash, that can't always be true. There's already a project to try and find collisions.

  3. It's all about collision by tepples · · Score: 1 · on Indiana First With Computerized Grading

    There we go again, taking my perfectly funny post and not recognizing it for humor.

    That's probably just my autism acting up.

    I agree that there exists no way to reconstitute a particular A quality text from just a grade or any other hash value, as a hash value is necessarily a lossy compression of a text. However, my point relates to a different problem of finding a collision, roughly defined as any text with a known hash value. MD4 is already analytically broken, and MD5 is heading that way. Because of the nature of the autograder hash (better English means a higher hash value), one could probably find a collision using a bit of chatbot tech.

  4. I like the Md5Crk applet model by Gollum · · Score: 4, Interesting · on Can You Spare A Few Trillion Cycles?

    MD5Crk.com has an applet on their site that does distributed calculations so long as it is visible in the browser (and assuming that you have specifically permitted it to do so). They are trying to find a collision to demonstrate that MD5 is insecure.

    This is great for a simple calculation that returns simple results (e.g.MD5), but probably wouldn't work in a situation where you have to have lots of data to work from. Of course, if you can break it down sufficiently, it might work, and I guess he has already done the work in figuring out how to break it down and recombine the results.

    See MD5Crk for the applet in question.

  5. MD5CRK by tepples · · Score: 1 · on Probable Solution Found for ECC2-109 Challenge

    I guess we have a bunch of potential recruits for the MD5CRK project (mentioned here), no?

  6. Re:MD5CRK boneheaded by Ed+Avis · · Score: 2, Interesting · on Slashback: Flashmob, Currency, Verification
    The definition of collision-resistent is that you cannot find ANY inputs x,y st x!=y and H(x) == H(y). None. No exceptions.
    In other words, that the function H is injective. But no message digest function producing a fixed-length digest from an arbitrary-length input can have such a property.
    Lets say I could easily generate MD5 collisions on 'random-looking' 128-bit strings ... Would MD5 be considerd broken?
    It depends on how you were doing it 'easily'... if you simply had a great deal of brute force to apply, then you could apply the same brute force to SHA-1 or any other message digest function. Only if you have some way of finding collisions which is better than brute force would this be a weakness in the digest function. (Of course, one can imagine a trivially weak message digest that has only 'A' and 'B' as possible outputs; for that algorithm even a brute force attack is easy enough to worry about, but this isn't the case for MD5 as far as I can tell.)

    Looking at the method MD5CRK will be using, it seems they'll just be brute-forcing MD5 by running it in a feedback loop to find a cycle (which must exist). As they say, this could be applied to any function which has finite range and domain (assuming that there is some reasonable mapping from domain back to range: in this case, they can both be treated as strings). Exactly the same technique could be applied to SHA-1. Do they simply mean that SHA-1 has a larger range of output values, so its cycles are probably longer and harder to find?
  7. Re:MD5 colision demonstration. by jlcooke · · Score: 1 · on Slashback: Flashmob, Currency, Verification

    the calculation time would not 'skyrocket'... but it does increase to a point where software is not the proper medium.

    In hardware, a 128bit collision can be accomplished in 24 days on a $100,000USD peice of hardware. Read more about this on The site.

  8. Fatal flaw in the MD5CRK algorithm by leob · · Score: 1 · on Slashback: Flashmob, Currency, Verification

    As described in their FAQ, they need a cycle that contains a Distinguished Point. But it is not guaranteed - there might as well be a simple fixed point or a small cycle that does not contain any DPs. They do not address this in the FAQ at all! The clients may be stuck in loops without sending anything to the server (having effectively found a collision), but the organizers will have no idea.

  9. Slashdot that distributed computing team! by focitrixilous+P · · Score: 1 · on Slashback: Flashmob, Currency, Verification

    So yeah, someone has to start a slashdot team. I mean, we owe it to them for destorying their site a while back.
    Join!