Re: [secdir] sec-dir review of draft-ietf-sieve-autoreply-02

[Barry Leiba <[e-mail]>]

Off list, Derek and I had a couple of exchanges, and Derek suggested
the following text, which I think is fine, and which I will add to my
working version of the document:

----------------------
 An autoresponder can cause leaks of other pieces of information,
 including potentially providing the ability to attack cryptographic
 keying material.  For example, using the time it takes to perform an
 cryptographic operation an attacker may obtain information about the
 secret key.  An autoresponder that doesn't take timing into account
 could accidentally leak this kind of information.

 Moreover, if an autoresponder script returns the results of a
 cryptographic operation that could also provide an attack vector.  For
 example, if a script returns the results of a decryption operation, an
 attacker can send an arbitrarily encrypted message and use the results
 as a chosen cyphertext attack to decode the encryption key.  Authors
 of scripts should be careful in what information they return to
 senders.
----------------------

Barry