Re: Best means to block MSN Messenger, AIM and other chat programs?

From: ktabic (lists@realitysuxs.co.uk)
Date: 02/21/02 

Date: Thu, 21 Feb 2002 20:25:34 +0000
To: security-basics@securityfocus.com
From: ktabic <lists@realitysuxs.co.uk>

TBH, you don't really have that much of a chance blocking these programs by
port, as three of them (I haven't used Yahoo) are perfectly capable of
going though other ports, aside from the default port numbers (I have seen
AIM using port 53 and port 80 to make it's connection)
You would probably have more luck at blocking the addresses the programs
connect to, preferably by name, although IP address would work to.
(Although, IIRC, the IP addresses AOL assigns to their logon server change
regularly, so nmae is better)
HtH
ktabic

At 11:31 20/02/2002 -0500, you wrote:
>Hello,
>I am using both filtering software and Firewall (GNat Box) to try to
>block out the use of several chat programs. On the FW I have blocked
>ports:
>4000 - ICQ
>1863 - MSN Messenger
>5050 - AOL and
>5190 for Yahoo
>After having set up the blocking rule, I then tested MSN Messenger in
>the system. Problem being that it was still accessible.
>Any suggestions as to how to block the use of the programs at the
>firewall would be greatly appreciated. 

-- 
Don't even go there

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