Re: MIDRANGE-L Digest V4 #261

[Jim Langston <jlangston@xxxxxxxxxxxxxxxx>]

Just a note, if you are only blocking specific ports, you have
your job cut out for you.  It is much better to block all ports
and then just enable those ports that are needed.  But, since
you are doing it this way make sure you also block out ports
31337 and 12345.

31337 is used by the Trojan Back Orafice and 12345 is used by
the Trojan NetBus.  Both of these Trojans work in about the same
way, the same way PC Anywhere does.  When run and installed just
about anyone can use your PC from anywhere on the internet.

Regards,

Jim Langston



Date: Wed, 21 Mar 2001 12:07:30 -0600
From: "Haase, Justin C." <Justin.Haase@Kingland.com>
Subject: RE: blocking ports

Ask AOL, Yahoo, etc.  Or just check the preferences tab.  They have that
information available to the user (and available to be changed).  And the
standard port for AOL IM is 5190.

Justin C. Haase 
Midrange Systems Engineer - Kingland Systems Corporation 
IBM Certified AS/400 Systems Administrator 
Microsoft Certified Professional 
phone - 641.355.1035 
fax - 641.355.1099 
cellular - 641.430.6381 
pager - 641.422.3023 
e-mail - justin.haase@kingland.com 
alpha page - 5550923.beeper@pager.beeperpeople.com 

- -----Original Message-----
From: Angela Wawrzaszek [mailto:wawrzaszeka@AUSTEEL.com]
Sent: Wednesday, March 21, 2001 11:22 AM
To: Midrange Mail List (E-mail)
Subject: blocking ports


The instant messengers that come with many browsers like AOL create a
security problem.  We would like to block the use of instant messengers by
blocking the port through TCP/IP that they come in on.  Does anyone know how
to determine what port these messengers use?  Or any other way to prevent
use of these.   Monitoring that no one installs one on their PC would be a
nightmare,  and a full time job. 
Angie Wawrzaszek 
M.I.S. Department
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