On 2017-04-20 01:43:11 (-0700), J. Johnson <[email protected]> wrote:
A while back I was wondering why certain spammers kept hitting our
'postmaster' account, then i realized there were multiple recipients.
It seems like the other recipients ride in on the back of 'postmaster',
then are free to go there individual ways. Does anyone know if that is
true? And if so, how can the additional recipients be suppressed?
It depends on where you whitelist postmaster. If you whitelist by
checking the To: header in `header_checks`, the message is likely to
also be delivered to anyone else in the To: header.
With `check_recipient_access` in `smtpd_{sender,recipient}_restrictions`
you can exempt mail with an envelope recipient postmaster from other
checks. E.g.:
main.cf:
smtpd_sender_restrictions =
[...]
check_recipient_access pcre:$config_directory/access_recipient.pcre
check_spf
access_recipient.pcre:
/^postmaster\@/ OK
The above would bypass `check_spf` for messages directed at postmaster
but the `header_checks` still run.
I would only list things in `header_checks` that are really egregious
and which no mail to postmaster@ is going to convince me is legitimate.
Philip
--
Philip Paeps
Senior Reality Engineer
Ministry of Information
