Exim - Stop user from sending email with fake FROM address

Posted on 2011-04-21
Last Modified: 2012-05-11
My server host multiple domains, I have found some users sending spam, they login to SMTP using account '' but sending email with SMTP FROM is How do I stop that emails?
Question by:NganPham
    LVL 39

    Accepted Solution

    Adding this to the acl for receipt to... (that follows the last mail from...)
             authenticated = *
             condition     = ${if !eqi{$authenticated_id}{$sender_address}}
             message       = Invalid authentication (you can only send From:$authenticated_id)
             log_message   = acl_check_rcpt Invalid authentication (From:$sender_address, Auth:$authenticated_id)

    Or check chapter 44 of the exim specification:

    on control = submission.

    Author Closing Comment

    The solution requires some modification to allow special case such as WebMail on the same server (WebMail sending emails without authentication).

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