Ethical Hacking

Learn to find vulnerabilities before the bad guys do! Gain real world hands on hacking experience in our state of the art hacking lab. Course designed and taught by expert instructors with years of penetration testing experience. 12 student maximum in every class. Certification attempt included in every package.
Computer Forensics Training at InfoSec Institute

Gain the in-demand skills of a certified computer examiner, learn to recover trace data left behind by fraud, theft, and cybercrime perpetrators. Discover the source of computer crime and abuse at your organization so that it never happens again. All of our class sizes are guaranteed to be 12 students or less to facilitate one-on-one interaction with one of our expert instructors.




Network Security Focus-Microsoft
[Top] [All Lists]

Re: Subdomain security

Subject: Re: Subdomain security
Date: Thu, 16 Dec 2004 11:29:07 -0500
Hello Oren -

First - I would like to state that I feel sorry for you and your
situation.... not an easy one to over come. Management that is....

Well, I would start out by asking if you can set up a site-to-site VPN?
That would be the most secure way of implementing your solution. If you
opened all the ports needed to have a forest root talk to a sub domain, you
might as well not have a firewall.

Here is a small list of the ports that I am talking about -
42           wins        TCP/UDP
53           domain            TCP/UDP
88           kerberos
123          ntp         UDP
135          loc-srv           TCP/UDP
137          nbname            TCP/UDP
138          nbdgram           UDP
139          nbsess            TCP

Now - take the last few ports...those would be the main ones that would
open up your network to just about every virus that targets Microsoft
systems.... anyone else on this list would agree that 135/137 are the worst
ports to open to the outside world.

Again, I would suggest getting a site-to-site tunnel working - any other
way would be disasterous for your organization. Just do a quick google for
ports used by Trojans....that should stop all discussions. Unless they
(management) thinks that AV will stop those ....

Good luck!
Rich



|---------+---------------------------->
|         |           Oren Held        |
|         |           <oren@held.org.il|
|         |           >                |
|         |                            |
|         |           12/15/2004 06:24 |
|         |           PM               |
|         |                            |
|---------+---------------------------->
  
---------------------------------------------------------------------------------------------------------------------------------------------|
  |                                                                             
                                                                |
  |       To:       focus-ms@securityfocus.com                                  
                                                                |
  |       cc:                                                                   
                                                                |
  |       Subject:  Subdomain security                                          
                                                                |
  
---------------------------------------------------------------------------------------------------------------------------------------------|




Hello,

I have to install a *secure* windows domain inside an insecure network.
This means that my domain will be behind a firewall ofcourse.

Now, I've got two possibilities for the domain configuration:
Option 1: My domain would actually be a subdomain inside the insecure
forest.
Option 2: Create a totally new forest.

So, surely option #2 is more secure, but the management pushes to
choosing option #1. so.. few questions about option #1:

a. Which ports should be opened by the firewall in order for the
subdomain to function well but be the most secure? Any references?

b. Does an admin (a member of the Enterprise Admin group) from the
root-domain have access to my subdomain? Can I prevent it at all?

c. Do you know any networks that implement option #1 with a firewall and
think they're quite secure from the other domains, or is it a totally
twisted idea?

Thanks a lot people,

 - Oren


---------------------------------------------------------------------------
---------------------------------------------------------------------------





---------------------------------------------------------------------------
---------------------------------------------------------------------------

<Prev in Thread] Current Thread [Next in Thread>