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<DIV dir=ltr align=left><SPAN class=745205415-30012004><FONT face=Arial
color=#0000ff size=2>I don't about anyone else but I've used telnet as a diag
tool for investigating smtp problems. It allows you to see the
responses in realtime when you type in the proper smtp commands. I use
ehloe, mail from, and recpt to quite a bit when
testing. </FONT></SPAN><SPAN class=745205415-30012004><FONT
face=Arial color=#0000ff size=2>You can telnet to practically any port you want
it. It just a matter of what the server daemon does with the commands
given to it.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=745205415-30012004></SPAN> </DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
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<FONT face=Tahoma size=2><B>From:</B> MailScanner mailing list
[mailto:MAILSCANNER@JISCMAIL.AC.UK] <B>On Behalf Of </B>Ugo
Bellavance<BR><B>Sent:</B> Friday, January 30, 2004 10:06 AM<BR><B>To:</B>
MAILSCANNER@JISCMAIL.AC.UK<BR><B>Subject:</B> Re: Port 25
vulnerability<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><SPAN class=306200415-30012004><FONT face=Arial color=#0000ff size=2>telnet
hostname 25 doesn't talk to the telnet server, it talks to the smtp
server. You cannot prevent this. If you block port 25, you cannot
receive mail. What you can do is prevent relaying.</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Message d'origine-----<BR><B>De :</B> taz
[mailto:taz@AZTEK-ENG.COM]<BR><B>Envoyé :</B> Friday, January 30, 2004
10:05 AM<BR><B>À :</B> MAILSCANNER@JISCMAIL.AC.UK<BR><B>Objet :</B>
Port 25 vulnerability<BR><BR></FONT></DIV>
<DIV><FONT face=Arial size=2>I have a question about mail and port 25 in
general. I know that this is really not on the mailscanner subject so if
I don't get an answer that is ok. There are lots of servers that accept
email, but don't allow you to telnet to port 25. Since port 25 is a port
that mail talks on how does one secure this port to only allow email to talk
to it and not allow the "telnet hostname 25" action. I know in this case
telnet is disabled on the mail server. Sorry for being so dopey on this
one.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks,</FONT></DIV>
<DIV><FONT face=Arial size=2>Travis</FONT></DIV></BLOCKQUOTE></BODY></HTML>