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Re: More then 2800 spams from the list...

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On Tue 20 Mar 2018 at 08:28:20 (-0400), Greg Wooledge wrote:
> P.S. someone said that bounces are generated using the Reply-To: header.
> This is incorrect (or at least, would be a violation of the protocols).
> Bounces are sent to the envelope sender address (the one given by the
> sender during the SMTP session), without looking at the message itself.
> 
> Of course, the envelope sender is just as easy to forge as the
> Reply-To: header is.  The sender only needs to lie about who it is.
> The receiver has no way to verify the address, other than "yeah, that
> domain exists in DNS".

But if that IP address sends loads of undeliverable mail,
why not just block it? I was under the impression that
that's what IP address blacklisting was all about.

> That's how backscatter (a.k.a. "joe-jobbing") works.  The spammer
> sends mail to an invalid address and lies about the envelope sender
> address.  The receiver generates a bounce to the forged envelope
> sender address.  Voila, spam sent -- by the poor schmuck in the middle
> who was just trying to follow the SMTP protocol properly.  The only
> one who can identify the actual sender is the one who generated the
> bounce, and the only identifying information that system has is the
> IP address from which the message was sent.  Everything else (envelope
> sender, message headers, message body) is fabricated.

Cheers,
David.

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Thread

More then 2800 spams from the list... "Michelle Konzack" <linux4michelle@tamay-dogan.net> - 2018-03-19 14:00 +0100
  Re: More then 2800 spams from the list... Jonathan Dowland <jmtd@debian.org> - 2018-03-19 14:20 +0100
    Re: More then 2800 spams from the list... Gene Heskett <gheskett@shentel.net> - 2018-03-19 15:50 +0100
      Re: More then 2800 spams from the list... <tomas@tuxteam.de> - 2018-03-19 15:50 +0100
        Re: More then 2800 spams from the list... Cindy-Sue Causey <butterflybytes@gmail.com> - 2018-03-19 16:10 +0100
          Re: More then 2800 spams from the list... Richard Owlett <rowlett@cloud85.net> - 2018-03-19 16:30 +0100
            Re: More then 2800 spams from the list... "Michelle Konzack" <linux4michelle@tamay-dogan.net> - 2018-03-19 16:40 +0100
              Re: More then 2800 spams from the list... Jim Popovitch <jim@k4vqc.com> - 2018-03-19 17:00 +0100
              Re: More then 2800 spams from the list... <tomas@tuxteam.de> - 2018-03-19 17:30 +0100
                Re: More then 2800 spams from the list... Miles Fidelman <mfidelman@meetinghouse.net> - 2018-03-19 18:50 +0100
                Re: More then 2800 spams from the list... Tony van der Hoff <lists@vanderhoff.org> - 2018-03-19 19:20 +0100
                Re: More then 2800 spams from the list... <tomas@tuxteam.de> - 2018-03-19 19:30 +0100
                Re: More then 2800 spams from the list... "Michelle Konzack" <linux4michelle@tamay-dogan.net> - 2018-03-19 19:40 +0100
          Re: More then 2800 spams from the list... Gene Heskett <gheskett@shentel.net> - 2018-03-19 16:40 +0100
          Re: More then 2800 spams from the list... Curt <curty@free.fr> - 2018-03-19 18:20 +0100
      Re: More then 2800 spams from the list... Richard Owlett <rowlett@cloud85.net> - 2018-03-19 16:00 +0100
  Re: More then 2800 spams from the list... Karol Augustin <karol@augustin.pl> - 2018-03-19 19:40 +0100
    Re: More then 2800 spams from the list... Nick Boyce <nick@steelyglint.org> - 2018-03-19 22:20 +0100
      Re: More then 2800 spams from the list... Karol Augustin <karol@augustin.pl> - 2018-03-19 22:40 +0100
    Re: More then 2800 spams from the list... Joe <joe@jretrading.com> - 2018-03-19 23:30 +0100
      Re: More then 2800 spams from the list... <tomas@tuxteam.de> - 2018-03-20 09:00 +0100
        Re: More then 2800 spams from the list... Joe <joe@jretrading.com> - 2018-03-20 10:30 +0100
          Re: More then 2800 spams from the list... <tomas@tuxteam.de> - 2018-03-20 10:50 +0100
          Re: More then 2800 spams from the list... Greg Wooledge <wooledg@eeg.ccf.org> - 2018-03-20 13:30 +0100
            Re: More then 2800 spams from the list... David Wright <deblis@lionunicorn.co.uk> - 2018-03-20 14:40 +0100
              Re: More then 2800 spams from the list... Greg Wooledge <wooledg@eeg.ccf.org> - 2018-03-20 14:50 +0100
          Re: More then 2800 spams from the list... "Michelle Konzack" <linux4michelle@tamay-dogan.net> - 2018-03-20 20:00 +0100
            Re: More then 2800 spams from the list... Brian <ad44@cityscape.co.uk> - 2018-03-21 01:20 +0100
              Re: More then 2800 spams from the list... Brad Rogers <brad@fineby.me.uk> - 2018-03-21 08:10 +0100

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