Loading ...
Sorry, an error occurred while loading the content.
 

Re: Question about "spoofing" emails.

Expand Messages
  • mouss
    ... to make him happy, use maildrop to replace the From header... ... to stop (reduce the number of) spam, use a spam filter together with (safe) smtpd checks.
    Message 1 of 9 , Mar 1, 2007
      Juan Pablo Calomino wrote:
      > --- MrC <lists-postfix@...> escribió:
      >
      >
      >>> I have one question for you.
      >>>
      >>> How do you do to avoid this kind of thing?
      >>>
      >>> 220 -Empresa de Servicios - XXXXXXX
      >>> helo mundo
      >>> 250 SERVER02.xxxxxxxx.com.ar
      >>> mail from: <nobody@...>
      >>> 250 Ok
      >>> rcpt to: <john.user@...>
      >>> 250 Ok
      >>> data
      >>> 354 End data with <CR><LF>.<CR><LF>
      >>> FROM: John User <john.user@...>
      >>> TO: <john.user@...>
      >>> SUBJECT: Nada
      >>>
      >>> Muerte!
      >>> .
      >>> 250 Ok: queued as 972C55865D
      >>>
      >>> I think that it's too difficult to get rid of this
      >>>
      >> type of
      >>
      >>> mails, filtering may reject valid emails...
      >>>
      >>> I hear any suggestions!
      >>>
      >> What specifically is "this kind of thing" ? The
      >> "mundo" HELO parameter?
      >> The "nobody@..." MAIL FROM envelope?
      >>
      >> Please be more specific about what you are trying to
      >> reject.
      >>
      >> MrC
      >>
      >>
      >>
      >
      > Sorry, I'm talking about the DATA part:
      >
      > data
      > FROM: John User <john.user@...>
      > TO: <john.user@...>
      > SUBJECT: Nada.
      >
      > John User may think that his mailbox is being used,
      > because in the mail he sees that the sender is
      > himself, and he doesn't know about MIME.
      > I explain that it is fake, so he asks me to try to
      > stop this "spoofed" emails.
      >

      to make him happy, use maildrop to replace the From header...


      > And here I am, trying to find ways to stop these
      > mails, without stopping valid mails.
      >

      to stop (reduce the number of) spam, use a spam filter together with
      (safe) smtpd checks. only when you get a satisfactory level of spam
      filtering should you look for improvement or for "hard" (unsafe) checks.
    Your message has been successfully submitted and would be delivered to recipients shortly.