Re: [SLUG] identifying open relays

["Gnuthad" <slug-list@xxxxxxxxxxxxxx>]

On 15 Sep 2001, at 15:04, Ken Foskey wrote:

> Rick Moen wrote:
> > 
> >   220 uncle-enzo ESMTP Exim 3.31 #1 Fri, 14 Sep 2001 17:44:17 -0700
> >   HELO linuxmafia.com
> >   250 uncle-enzo Hello rick at uncle-enzo [198.144.195.186]
> >   MAIL FROM: foo@xxxxxxx
> 
> What happens if you use foo@xxxxxxxxxxxxxx?

Shouldn't a secure email server check for the existance of a local 
address before handling the email?

> >   250 <foo@xxxxxxx> is syntactically correct
> >   RCPT TO: bar@xxxxxxx
> >   550 relaying to <bar@xxxxxxx> prohibited by administrator
> 
> I have noticed spammers coming on my public address (waratah@xxxxxxxxxx) 
> appearing as leeloo@xxxxxxxxxx.   They must be getting a bit smarter.

I've also had them using <> as the sender with a local acount as the 
recipient. For me personally, I don't allow non-local people to relay 
through my server. My server, Mercury (Winblows, but no flames 
please, I'm rebuilding my Linux server to a bigger/faster system), 
only allows localhost and my private network addresses to send email 
to non-local recipients. This may or may not be suitable for others, 
but it's how I solved a lot of my problems.


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