Re: Vulnerability: known crypto algo + known MD5 value

This question makes no sense.

A hash algo like SHA-256 takes an any input and makes a unique (unique in theory
and most of reality) fixed-length output.
An encryption key takes an input and makes an output of varying length. In
asymmetric/public key encryption the first (public) key encrypts an input and
(if the system works well) only the other (private) key decrypts.

Encrypting a SHA-256 hash (which is itself a string of characters) is
functionally the same as encrypting your name, the king james bible, or any
other string of characters. (OK, slow CPU's would take longer to hash the bible
than a few character input such as a name)

Make sense?

~David~

claude wrote:
Sorry! Let me take that back. Assuming you are working with asymetric
keys (where none of the 2 keys are known). Now, if we used one of the
asymetric key to encrypt the SHA-256 result, how difficult would it be
to find the asymetric key used if you can generate as many combinaison
as wanted of SHA-256 result with its corresponding RSA 1024 encrypted
value ?

Sorry again for the confusion.

Claude

.

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