ISPConfig + Perfect Setup Ubuntu 5.10 + Smtp SPAM problems

Discussion in 'Installation/Configuration' started by lyndros, Apr 12, 2006.

  1. lyndros

    lyndros New Member

    HI all guys,

    i configured my server a month ago but im havin problems with spam, i just followed all the steps in perfect setup ubuntu 5.10, but anyone can send emails throught smtp without authentification.


    For example i telnet to my server to port 25(i tried from an outside ip and it worked).

    So when i look to my mail logs, im noticing that some people is using my server to send emails....

    anyone could help me?

    thks in advanced :p
     
  2. till

    till Super Moderator

    First, did you try to send emails to a domain on your server or to an external domain. Your server is only an open relay if someone can send email to e.g. a gmail account without authentication.

    Please post your postfix main.cf file here.
     
  3. falko

    falko Super Moderator

    What's the output of
    Code:
    telnet localhost 25
    and then
    Code:
    ehlo localhost
    ?
     
  4. lyndros

    lyndros New Member

    this is my output to ehlo :p, i think its right because is starttls and AUTH...

    501 Syntax: EHLO hostname
    ehlo server.com
    250-server1.mydomain.com
    250-PIPELINING
    250-SIZE 10240000
    250-VRFY
    250-ETRN
    250-STARTTLS
    250-AUTH LOGIN PLAIN
    250-AUTH=LOGIN PLAIN
    250 8BITMIME

    this is my main.cf from /etc/postfix

    # See /usr/share/postfix/main.cf.dist for a commented, more complete version

    smtpd_banner = $myhostname ESMTP $mail_name
    biff = no

    # appending .domain is the MUA's job.
    append_dot_mydomain = no

    # Uncomment the next line to generate "delayed mail" warnings
    #delay_warning_time = 4h

    myhostname = server1.mydomain.com
    alias_maps = hash:/etc/aliases
    alias_database = hash:/etc/aliases
    myorigin = /etc/mailname
    #mydestination = server1.mydomain.com, localhost.mydomain.com, localhost
    relayhost =
    mynetworks = 127.0.0.0/8
    mailbox_size_limit = 0
    recipient_delimiter = +
    inet_interfaces = all
    mailbox_command =
    smtpd_sasl_local_domain =
    smtpd_sasl_auth_enable = yes
    smtpd_sasl_security_options = noanonymous
    broken_sasl_auth_clients = yes
    smtpd_recipient_restrictions = permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination
    smtpd_tls_auth_only = no
    smtp_use_tls = yes
    smtpd_use_tls = yes
    smtp_tls_note_starttls_offer = yes
    smtpd_tls_key_file = /etc/postfix/ssl/smtpd.key
    smtpd_tls_cert_file = /etc/postfix/ssl/smtpd.crt
    smtpd_tls_CAfile = /etc/postfix/ssl/cacert.pem
    smtpd_tls_loglevel = 1
    smtpd_tls_received_header = yes
    smtpd_tls_session_cache_timeout = 3600s
    tls_random_source = dev:/dev/urandom
    home_mailbox = Maildir/

    virtual_maps = hash:/etc/postfix/virtusertable

    mydestination = /etc/postfix/local-host-names
     
    Last edited: Apr 13, 2006
  5. till

    till Super Moderator

    Did you try to send emails to a domain on your server or to an external domain?
     
  6. falko

    falko Super Moderator

    There are three scenarios when you don't have to authenticate when you want to send mails:
    1. You're sending directly from the server, e.g. with webmail.
    2. You're sending to e recipient whose mailbox is on the server.
    3. You're sending from a computer that is within mynetworks in /etc/postfix7main.cf.
     
  7. lyndros

    lyndros New Member

    ok, falko i understand but my networks only responds to 127.0.0.0/8 so if i tried from a machine from my local network 192.168.1.x , i must auth because it's not on my networks and i can send mails to any external domain, like hotmail, gmail etc...

    thks in advanced :)
     
  8. falko

    falko Super Moderator

    What's in your mail log when yout try to send to an external recipient?
     
  9. lyndros

    lyndros New Member

    falko i think that the problem is solved :) i dont know how :(

    another question this is normal ?

    220 server1.example.com ESMTP Postfix
    ehlo test.com
    250-server1.example.com
    250-PIPELINING
    250-SIZE 10240000
    250-VRFY
    250-ETRN
    250-STARTTLS
    250-AUTH LOGIN PLAIN
    250-AUTH=LOGIN PLAIN
    250 8BITMIME
    mail from: test@example.com
    501 Bad address syntax
    mail from: example@test.com
    501 Syntax: MAIL FROM: <address>
    MAIL FROM: TEST@example.com
    250 Ok
    RCPT TO: test@gmail.com
    554 <test@gmail.com>: Relay access denied

    but when the auth is require? if i dont auth this is the message ?


    thks in advanced
     
  10. till

    till Super Moderator

    SMTP-Auth is required everytime you send an email to a domain that is not hosted on your server and where the sending host is not in mynetworks.
     
  11. falko

    falko Super Moderator

  12. lyndros

    lyndros New Member

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