Webone blocking port 25??

Jeremy jepri at webone.com.au
Fri Jul 26 09:31:53 EST 2002

> Not complete and utter bullshit, actually. If all they were doing was
> checking for a valid domain in the From: header, they would still be
> an
> open relay (any script kiddie or spamster can invent a
> randomcharacters at yahoo.com email address which will pass that test).
> Try
> relaying through webones smtp host using a real hostname from outside
> the webone network, and I'll bet you go nowhere (if you don't, I
> suggest
> phoning webone immediately and pointing out to them that they are
> going
> to be blacklisted really soon if they don't fix it).

My apologies, I should have said it was mostly right, just implying 
something not quite right.  They do, of course, authenticate relaying 
by IP, but also by valid domain name.  The interesting bit is that they 
don't give an SMTP error when they do so.  They acept the mail then 
drop it later.

220 cts04.webone.com.au ESMTP Sendmail 8.11.6/8.11.6; Fri, 26 Jul 2002 
09:26:02 +1000
helo jepri
250 cts04.webone.com.au Hello dial-ctt03-248.webone.com.au 
[], plea
sed to meet you
MAIL FROM: <jepri at fakedomain>
250 2.1.0 <jepri at fakedomain>... Sender ok
RCPT TO:<jepri at webone.com.au>
250 2.1.5 <jepri at webone.com.au>... Recipient ok
354 Enter mail, end with "." on a line by itself
Hello test
250 2.0.0 g6PNQWH03853 Message accepted for delivery
221 2.0.0 cts04.webone.com.au closing connection

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