Re: [exim] Blocking non-authenticated senders

David Woodhouse wrote:
> On Tue, 2007-02-20 at 15:38 +0100, Peter Velan wrote:
>> I don't see a situation where a foreign server sends me a legit email
>> with envelope-from = "localpart@???"?
>
> If there is any external email address for which email is just
> automatically forwarded to your systems, and if any of your users
> send mail to that address, then it'll happen.

On the other hand, the vast majority of messages that have identical
envelope FROM and RCPT addresses are spam (here at least). So IF you
provide your users with a per-user whitelist system then you could
consider blocking that class of messages - that way you have a cheap and
effective check that your users can easily bypass if they need to.

You may also want to consider blocking
nonexistent-local-part@???, but I think David is right, it's
probably wise to steer away from a "blanket" block on
any-address@??? !

Regards

Richard

--
Richard Rogers
IT Development and Innovation Manager
Staffordshire University


The information in this email is confidential and is intended solely for the addressee. Access to this email by anyone else is unauthorised.



If you are not the intended recipient, any disclosure, copying, distribution or any action taken or omitted to be taken in reliance on it, except for the purpose of delivery to the addressee, is prohibited and may be unlawful. Kindly notify the sender and delete the message and any attachment from your computer.