Re: I-D ACTION:draft-ietf-smime-rcek-01.txt

[Stephen Farrell <stephen.farrell@xxxxxxxxxxxx>]

Thanks Mike,

Will add words to that effect.

Stephen.

> Mike Just wrote:
> 
> Hi Stephen, Sean,
> 
> Possibly another item worth including in the Security Considerations section. Suppose MSG1 is sent
> to a set S1 of users. In the case where MSG2 is sent to only a subset of users in S1, all users
> from S1 will still be able to decrypt MSG2 (since MSG2.KEK is computed only from MSG1.CEK).  I
> don't think you intended for your solution to be used for such dynamic recipient sets, but it
> might be worth explicitly mentioning this unfortunate side-effect of key re-use in any case.
> (Might be enough to mention that the recipient lists must be the same for each message.)
> 
> Mike J.
> 
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