On Tue, 31 Jul 2007, NetComrade wrote:
> We have whitelisted our domain, but now we have spam coming from
> users that claim they're in our domain.
>
> What's the best way to fight it?
How exactly did you "whitelist your domain"? whitelist_from is a
last resort even though it's the most appealing. You really want to
use whitelist_from_rcvd or whitelist_from_spf.
Publish SPF records; that will help you out as well as everyone else.
If you can guarantee that mail addressed from your domain will only
ever originate at your mail server, you can put some mechanism in
place in the MTA to reject any message with your domain in the From
envelope address unless it originates in your local network. How you
do this depends on which MTA you use.
I can make suggestions for sendmail; another place to ask if you
deside to do this would be the mailing list specific to your MTA.
--
John Hardin KA7OHZ
http://www.impsec.org/~jhardin/ jhardin@... FALaholic #11174 pgpk -a
jhardin@...
key: 0xB8732E79 -- 2D8C 34F4 6411 F507 136C AF76 D822 E6E6 B873 2E79
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