dovecot - Apr 2016 - How to filter spam with same to: and from: adress

Is it possible to create a filter somewhere to delete email that have same to:
and from: adress. All these email are forged using my domain name with always
different fictif user name. The only common point is that they have the same
user name in the from: and to: adress

Claude Gelinas agr.
Phyto Ressources Inc.

This is usually solved within your mta. In most simple setups, the MX server
receiving the mails should not accept mails for which it is responsible itself,
so your mailserver phyto.qc.ca should not accept mails with "from: any at
phyto.qc.ca" from other servers than what you defined (e.g. in
"mynetworks" if you are using postfix).
On the other hand, you should make sure that your users cannot send their mails
other than that linked to their accounts, so make sure joe at phyto.qc.ca cannot
send as maria at phyto.qc.ca ... if you are using postfix, you might have a look
at reject_sender_login_mismatch.

hope this helps,

infoomatic
> Gesendet: Donnerstag, 14. April 2016 um 13:32 Uhr
> Von: Claude <claude at phyto.qc.ca>
> An: "dovecot at dovecot.org >> dovecot dovecot.org"
<dovecot at dovecot.org>
> Betreff: How to filter spam with same to: and from: adress
>
> Is it possible to create a filter somewhere to delete email that have same
to: and from: adress. All these email are forged using my domain name with
always different fictif user name. The only common point is that they have the
same user name in the from: and to: adress
> 
> Claude Gelinas agr.
> Phyto Ressources Inc.