full-disclosure - SPAM and "undisclosed recipients"

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Message-ID: <245918211.1068898949@bluekoolade>
From: jd at ods.org (Jason DiCioccio)
Subject: SPAM and "undisclosed recipients"

Kristian,
  What you are seeing is that you were BCC'd on the message.  In the 
process of an email transaction there are multiple times at which 
recipients are specified.  There is one at the sender's mailserver, where 
he specifies every recipient that is going to receive his message.  He does 
this in the form of 'MAIL TO: <email@...ress>' and repeats it until all of 
the recipients have been listed.  The mail server then takes that 
information and connects to all the mail servers it must connect to in 
order to deliver the message to all of the recipients that the sender 
specified.  Now, as for what you see in your mail client:  That is the To: 
and CC: headers.  They are specified in the actual message data and are 
independent of the recipient information that the sender sends to his mail 
server.  So, the definition of a BCC (Blind Carbon Copy) really is just a 
recipient that does not get listed in the message header.  Instead, it is 
only sent to the mail server as part of the MAIL TO: command sequences. 
The most information you will likely be able to retrieve about who received 
the message is from your Received: headers.  You should be able to tell 
from there (depending on the mail server) which alias or address the sender 
actually specified when he attempted to send the message.  This can be 
handy if you have multiple aliases and are wondering which one the spam is 
getting to.

Hope this helped.

Regards,
-JD-

--On Saturday, November 15, 2003 11:10 AM -0500 Kristian Hermansen 
<khermansen@...technology.com> wrote:

>
>
> I have a small question about SPAM emails that are sent to "undisclosed
> recipients".  Does this just mean that the server stripped the header
> before sending it to my account?  I don't understand how it could make it
> to my server, let alone my email account, if nothing was specified.  Does
> this raise any security issues?
>
>
>
>
>
> Kristian Hermansen
>
> CEO - H&T Technology Solutions
>
> khermansen@...technology.com
>
>