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Email Spoofing

Discussion in 'E-mail Discussion' started by stronciy, May 20, 2018.

  1. stronciy

    stronciy Registered

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    Hi All,

    Please help me, I can send email through telnet how to prevent this ?

    I make this instruction but not work
    - Removed -

    So, when I open telnet end make this steps I can send email from any domain present on my server:
    Code:
    
    telnet
    ehlo example.com
    mail from: info@localdomain.com
    rcpt to: email@anydomain.com
    data
    Subject: My Telnet Test Email
    
    Hello,
    
    This is an email sent by using the telnet command.
    
    Your friend,
    Me
    
    .
    quit
    
    my system is:

    CENTOS 6.9 kvm [srv]
    WHM v68.0.38
     
    #1 stronciy, May 20, 2018
    Last edited by a moderator: May 20, 2018
  2. sparek-3

    sparek-3 Well-Known Member

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    Yep! Now you know how SMTP works.
     
  3. stronciy

    stronciy Registered

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    Thanks,
    But my question, how to disallow to send email through telnet (SMTP) without authentication ?

    This is my log, when I connect through telnet to my server and try to send email:
    Code:
    May 20 18:26:47 srv dovecot: lmtp(8977): Connect from local
    May 20 18:26:47 srv dovecot: lmtp(mail@domain.com): msgid=<idyab0guthw9sgjs-f7vhavlu8hk4z3ps-1ecc9acd0@domain.com>: saved mail to INBOX.Junk
    May 20 18:26:48 srv dovecot: lmtp(8977): Disconnect from local: Successful quit
    May 20 18:27:11 srv dovecot: lmtp(8977): Connect from local
    May 20 18:27:12 srv dovecot: lmtp(to@domain.com): msgid=unspecified: saved mail to INBOX
    May 20 18:27:12 srv dovecot: lmtp(8977): Disconnect from local: Successful quit
    
    
     
    #3 stronciy, May 20, 2018
    Last edited by a moderator: May 20, 2018
  4. cPanelMichael

    cPanelMichael Forums Analyst
    Staff Member

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    Hello @stronciy,

    It looks like you opened a support ticket for this topic (#9586143). Here's the response from one of our Technical Analysts:

    Thank you.
     
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