... From: Masoumeh Izadi To: Sent: Wednesday, May 30, 2012 1:14 PM Subject: Telnet not authenticating ... Well
Message 1 of 1
, May 31, 2012
----- Original Message -----
From: "Masoumeh Izadi" <izadi@...>
Sent: Wednesday, May 30, 2012 1:14 PM
Subject: Telnet not authenticating
> We have a postfix Email server . when someone telnet to port 25 on our
> server, it is possible to send email from any ID user1@ anydomain to any
> user2@ mydomain
> telnet x.x.x.x 25
> ehlo localhost
> mail from:user@anydomain
> sender OK
> rcpt to: user@mydomain
> recipient OK
> The question is that: Is there any solution to prevent this matter or
> somehow make postfix to authenticate the users telneting the server
> By the way, our email server is not an open relay server.
Well one thing you could do is to put your internal domains in a
sender_access map and make them auth enabled only and add the the changes to
your smtpd_sender_restriction in main.conf.
Postfix internal functions such as error notification among other things
doesn't seem to be interrupted by setting this.
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