A crazy thought?

[Anne & Lynn Wheeler]

Jim Dixon wrote:
> The CA certifies that X is your public key.  It doesn't know what your
> private key is.
> 
> If the CA starts handing out false public keys - which is the worst
> that it could do, right? - it will find itself instantly distrusted.
> Everybody in the world will be able to see that the CA used its private
> key to sign a false statement.  The offended party need only put the
> false declaration up on the Web.

CAs actually tend to certify that they were able to verify a supplied
digital signature with a supplied public key ... with the implication
that the entity supplied the signature & key ... had access to the
corresponding private key in order to generate the signature
(aka "something you have" authentication model).

CAs then may also certify that they were able to verify some amount
of other information related to the entity supplying the signature
and public key.

the existence of a certified digital certificate with a different
public key ... can be on the order of various kinds of identity
theft ... and as equally difficult to deal with.

for instance ... it may not be sufficient that you can prove that there
are two distinct, different digital certificates ... in the identity
theft scenario ... it may also going to require that the disputed
digital certificate couldn't possibly apply to you (which is more than
just that it is not the same as the digital certificate you are
owning up to).

previous posts in thread:
http://www.garlic.com/~lynn/aadsm27.htm#22 A crazy thought?
http://www.garlic.com/~lynn/aadsm27.htm#26 A crazy thought?

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