Re: SHA1 Question

From: Michael Amling (nospam_at_nospam.com)
Date: 03/31/05

  • Next message: Mxsmanic: "Re: SHA1 Question" 
    Date: Thu, 31 Mar 2005 04:16:10 GMT

    Igor Tebelev wrote:
    > Suppose I have some unknow sequence of 7 bytes.
    > Those bytes are encrypted using SHA1 which produces 20 bytes hash value
    > Of those 20 bytes first 12 are known.
    >
    > So, the question is: having first 12 bytes of SHA1 result is there anyway to
    > find original 7 bytes sequence used to produce that SHA? Brute force
    > solution is not acceptable: I'm looking for something fast. Any refferences
    > would be appreciated.

       Someone will correct me if I'm wrong, but AFAIK, brute force is the
    fastest way to find SHA-1 pre-images. If some sequences of 7 bytes are
    more likely than others (which you could not find out just from looking
    at the hash), try them first.

    --Mike Amling

  • Next message: Mxsmanic: "Re: SHA1 Question"

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