Re: [Exim] Preventing forged From: headers (exim 3.36)

Pàgina inicial
Delete this message
Reply to this message
Autor: David L. Harfst
Data:  
A: robl, Exim Users
Assumpte: Re: [Exim] Preventing forged From: headers (exim 3.36)
Robert Lister wrote:
>
> No users should send "from" my domain unless they were on a client from an
> IP address authorized to do so, inside this network. period.
>
> If they're outside my network, they shouldn't be sending me e-mail with my
> own domain in the "From:" headers. I want a filter to pick this up and
> throw it away (not reject it, but discard it, as the sender/From: header
> is of course forged, and so the bounce message goes to the list, usually
> quoting the spam.)
>


How about this:

I've got users who travel. They have a corporate email
account, but access is provided by an ISP, so their email
does not come from the corporate LAN, but they use their
corporate email address as their "From:".

Worse yet, many times they are sending to a customer, not
another employee, so it's actually relay mail with a forged
sender, since their outgoing mail is set to the corporate
mail server. But yet, legitimate.

Even myself - I have a laptop. I use an ISP at home to
access work. If can't send email using my corporate account,
I would have to keep juggling mail profiles. Not to mention
that even using the "Reply-To", some response email will
end up going to the ISP email account instead of the corporate.
Most of my users don't even bother to check their ISP email
account - they don't use it.

--
David L. Harfst                     Computerized Medical Systems
Senior Systems Engineer             St. Louis, Missouri
mailto:harfst@cms-stl.com           http://www.cms-stl.com