Then the gov't can do a handy man-in-the-middle(MITM) attack. They can distribute a different public key for you, and intercept messages, decrypt them, alter them if desired and reencrypt them with your proper public key.

Of course if the whole cyphertext is signed by its sender, then the signature would be invalidated. But the same sort of MITM stuff to the signature.

If you are willing to compromise one key to spy, compromising two is no big step to take.

This problem exists anytime you have one big repository of public keys. The only defense I know of is to have multiple, independent key repositories.


TGI says moo

In reply to Re^3: OpenID alternatives, what do you suggest by TGI
in thread OpenID alternatives, what do you suggest by zentara

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