Re: Complex Theoretical One Way Hash Question



Matthew Harrison wrote:
I wish to know if it is possible to embed an MD5 of an image (e.g. a
JPEG) in the image such that the MD5 is human readable in the image AND
is an MD5 of the modified image including the readable MD5.

I don't know of any way to do this. This would probably require breaking
the security (in particular, the one-wayness) of MD5. The problem is
that the hash depends on every bit of the image; but some bits of the
image depend on the hash; so you have a circular dependency that there
doesn't seem to be any easy way to break.
.



Relevant Pages

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