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Re: Re: getting 2822 protection as well as 2821 protection

2004-04-07 09:23:56
On Wed, 2004-04-07 at 10:59, Jim Ramsay wrote:
I propose a way of matching the Envelope to the Headers "within reason": 
  That is, if the domain is mostly the same, and the front-part is 
mostly the same, consider it "first-class".  For example, I think this 
could be considered close enough to say that an email is "first-class":

Envelope: i(_dot_)am-bounce-return(_at_)watson(_dot_)jimramsay(_dot_)com
From: i(_dot_)am(_at_)jimramsay(_dot_)com
Reply-to: i(_dot_)am-other-mailbox(_at_)jimramsay(_dot_)com
Sender: lack(_at_)holmes(_dot_)jimramsay(_dot_)com

So how would you differentiate the above example from this one:

Envelope: i(_dot_)am-spammer(_at_)jimramsay(_dot_)com(_dot_)spammer(_dot_)net
From: i(_dot_)am(_at_)jimramsay(_dot_)com
Reply-to: 
i(_dot_)am(_dot_)freshened(_dot_)on(_dot_)the(_dot_)spamlist(_at_)jimramsay(_dot_)com(_dot_)spammer(_dot_)net
Sender: i(_dot_)am(_at_)jimramsay(_dot_)com

Or something similar.  Not enough similarities?  Enough to consider it
'first-class'?  I think that if your doing interesting things with your
envelope, reply-to, etc., then we shouldn't try to detect this and still
classify it as 'first-class', it would simply fall into the
'second-class' bucket and still be seen by the user as probably
legitimate mail.  If we're getting into the business of classifying
mail, 'first-class' should be absolutely verifiable as legitimate and
anything else would be a lesser class.  In the example of using C/R
systems, it's an unfortunate side-effect that the addresses don't match.

-- 
Dustin D. Trammell
Vulnerability Remediation Alchemist
Citadel Security Software, Inc.