Postfix spam issue, is normal?

Hello,

here is/var/log/maillog:

(i replaced by asterisks something)

this entry is there many many times, deffered folder is like 200mb with some spam crap.

I want to ask how i can tighten my postfix settings to prevent above mentioned spam? is my postfix wrongly configured?

my /etc/postfix/main.cf

smtpd_client_restrictions =
smtpd_helo_restrictions =
smtpd_sender_restrictions =
smtpd_recipient_restrictions = permit_sasl_authenticated,
        permit_mynetworks,
        reject_unauth_destination,
        reject_non_fqdn_sender,
        reject_non_fqdn_recipient,
        reject_unknown_recipient_domain

Code (markup):

you see "smtpd_client_restrictions" are not set, is it what is wrong? how exactly it should look like? do i need to do any commands to reveal more the issue?

PS, i used online open relay testers like mxtoolbox.com/diagnostic.aspx and my server is not openrelay.

Thank you

 

Please kindly anyone help me discovere where is the hole in postfix / system?
Here are two example emails headers:
http://pastebin.com/ZXnk4q42

 

Have you setup spamassassin

 

i think its not installed, there is a script to install it on Zpanel server, but why should i use this, why do you think it would help in my case. Moreover i dont want to put higher load on server by spamd (assasin) processes..

 

I had same issue with postfis and sendmail. Then I moved to SMTP and all these problems are gone.
Perhaps some of the scripts you run (wordpress, vbulletin) when MySQL is gone are sending to much database error notificiations via postfix