Setting up SMTP-AUTH

[tristanlee85]

Since I can't figure out how to successfully stop relaying on my server, I've been informed that using SMTP-AUTH is the way to go so only I can relay through my server. I have ISPConfig already installed and I was reading the Postfix How-To here ( http://www.howtoforge.com/howto_postfix_smtp_auth_tls_howto ) but that's when you are starting from scratch to setup SMTP-AUTH. How would i go about setting this up on a ISPConfig system?

[till]

That is not the best howto for your ISPConfig server. Please configure your server as described in the perfect setup howto for your linux distribution.

[tristanlee85]

I did. I followed the Fedora Core 5 64-bit (even though I'm 32-bit) without issues. It says to see if everything is good, telnet to the SMTP server.

[tristan@localhost ~]$ telnet 192.168.1.130 25
Trying 192.168.1.130...
Connected to 192.168.1.130 (192.168.1.130).
Escape character is '^]'.
220 server.vasceria.com ESMTP Postfix
ehlo testing
250-server.vasceria.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH LOGIN PLAIN
250-AUTH=LOGIN PLAIN
250 8BITMIME


I am assuming that I should have to enter in a username/password to send mail out correct? I'm resorting to this because I can't seem to find any other way to block people from using me as a relay.

[till]

Please use this tool to check if your server allows relaying:

http://www.abuse.net/relay.html

[tristanlee85]

I think Falko gave me the link to that in the past and the results show that I'm good.

Connecting to www.plastikracing.net for anonymous test ...

<<< 220 server.vasceria.com ESMTP Postfix
>>> HELO www.abuse.net
<<< 250 server.vasceria.com
Relay test 1
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@abuse.net>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 2
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 3
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 4
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 5
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@[24.95.42.77]>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 6
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<securitytest%abuse.net@plastikracing.net>
<<< 554 <securitytest%abuse.net@plastikracing.net>: Relay access denied
Relay test 7
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<securitytest%abuse.net@[24.95.42.77]>
<<< 554 <securitytest%abuse.net@[24.95.42.77]>: Relay access denied
Relay test 8
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<"securitytest@abuse.net">
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 9
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<"securitytest%abuse.net">
<<< 554 <securitytest%abuse.net>: Relay access denied
Relay test 10
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net@plastikracing.net>
<<< 554 <securitytest@abuse.net@plastikracing.net>: Relay access denied
Relay test 11
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<"securitytest@abuse.net"@plastikracing.net>
<<< 554 <securitytest@abuse.net@plastikracing.net>: Relay access denied
Relay test 12
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<securitytest@abuse.net@[24.95.42.77]>
<<< 554 <securitytest@abuse.net@[24.95.42.77]>: Relay access denied
Relay test 13
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<@plastikracing.net:securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 14
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<@[24.95.42.77]:securitytest@abuse.net>
<<< 554 <securitytest@abuse.net>: Relay access denied
Relay test 15
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<abuse.net!securitytest>
<<< 554 <abuse.net!securitytest>: Relay access denied
Relay test 16
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<abuse.net!securitytest@plastikracing.net>
<<< 554 <abuse.net!securitytest@plastikracing.net>: Relay access denied
Relay test 17
>>> RSET
<<< 250 Ok
>>> MAIL FROM:<spamtest@plastikracing.net>
<<< 250 Ok
>>> RCPT TO:<abuse.net!securitytest@[24.95.42.77]>
<<< 554 <abuse.net!securitytest@[24.95.42.77]>: Relay access denied
Relay test result
All tests performed, no relays accepted.

Yet people are still using me to spam fake eBay e-mails. Road Runner only allows sending up to 1000 e-mails a day and if I get spammed, my limit is reached instantly and I can't send mail for another 24 hours.

[falko]

Well, this might mean that you have a vulnerable contact form/guestbook/whatever in one or more of your web sites that can be abused by spammers... :(

[tristanlee85]

The only form I have is at the bottom of my forums.

http://forums.plastikracing.net/index.php

The mail it sent to me, and it'd be hard to spam with the image verification.

[falko]

and it'd be hard to spam with the image verification.Well, it's possible for spam bots nowadays to crack the captchas... :(

[tristanlee85]

Could be, but they can't specify where to send the e-mail in that form. Anything entered in that form goes to phpbb@plastikracing.net.

[falko]

There's a problem with PHP's mail() function: it doesn't check if there are linebreaks in the parameters that you pass to it. Maybe that makes you contact form vulnerable.