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This draft is a work item of the S/MIME Mail Security Working Group of the IETF.
Title : Sender Authentication and the Surreptitious Forwarding
Attack in CMS and S/MIME
Author(s) : D. Davis
Filename : draft-ietf-smime-sender-auth-00.txt
Date : 01-Oct-01
By default, a CMS signed-and-encrypted document or message authenticates
only the document's originator, and not the person who encrypted the
document. This subtle limitation exposes CMS and S/MIME signed-and-encrypted
data to 'surreptitious forwarding.' Secure-messaging standards have treated
surreptitious forwarding as an insoluble problem of user carelessness, and have
long accepted the risk of this attack. This document discusses easy
cryptographic remedies for this attack, suitable for incorporation into the CMS
and S/MIME specifications. This document is an abridgement of [U2001].
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