Autor: Andy Smith Data: Para: exim-users Assunto: Re: [exim] Backscatter Spam Again. HELP PLEASE!
Grant,
SPF should help you, but you need to have SPF checking on your side and
those seeing you as a source of spam need
and SPF record in their DNS. The theory is that you recieve spam from for
example, andy@??? but its not really
from companyx.com its sent from a spammers machine. Currently if "to"
address doesnt exist you are sending an address
does not exist back to companyx.com, which is why you are being percieved as
a spammer. If you have SPF implemented
the theory is when the spam arrives with a forged from address, SPF will
check where the mail came from and if it is not
a legitamate mail server (IP address) of companyx.com the mail is rejected
and hence you will not send any address does
not exist mail to companyx.com (which is what you want),
thanks Andy.
----- Original Message -----
From: "Andy Smith" <a.smith@???>
To: <exim-users@???>
Sent: Wednesday, March 05, 2008 11:07 PM
Subject: Re: [exim] Backscatter Spam Again. HELP PLEASE!
> Hi,
>
> yeah, SPF isnt necessarily going to make a huge difference to everyone,
> but its one and only goal to to
> detect email with a spoofed/forged from address which is why I said i
> thought it would be effective in
> reducing the issue at hand. Actually I missread the email below slightly
> :P appologies, actually SPF needs
> to be implemented on the domains which are being targeted by the spammer
> as forged "from" addresses,
> if not already, and Grant needs to make sure he has something on Exim that
> will check SPF (ie
> spamassisin or I believe theres is a modded exim which natively supports
> it).
> Anyway, really its designed to combat this type of thing so I think its
> gota be worth sticking in,
>
> thanks Andy.
>
> ----- Original Message ----- > If you haven't done so already you should
> implement SPF for all domains
>> for which you send email. To be effective this also relies
>> on the recieving side server supporting SPF but its pretty widespread so
>> should have a very positive impact on your problem if
>> you arent already using it.
>
>>>
>>> Matt, Peter and all,
>>>No these are backscatter bounces.
>>>Non existent addresses on my server(s) are being sent SPAM with forged
>>>remote 'From:' addresses. Then, those spams are being bounced to the
>>>remote address' (from my servers)!
>>>-Grant
>>
>