Re: Interpreting the results of an NMAP scan

[infolookup () gmail com]

Dan,

It looks like the might be some port forwarding going on, that's why you are able to see the Exchange server from the 
outside, in order for you to access outlook web access you need port 443 or 80 depends on your setup, and in order to 
send or receive email you need port 25 smtp open.

As far as seeing the Linksys from the outside there should be a option to drop icmp probes, this will block pings, but 
if you set the correct scan type via nmap you might still find these ports since the a necessary for functionality.

Hope this helped!
Sent from my Verizon Wireless BlackBerry

-----Original Message-----
From: Dan Fauxpoint <danielfauxpoint () yahoo com>

Date: Wed, 22 Apr 2009 18:57:55 
To: <security-basics () securityfocus com>
Subject: Interpreting the results of an NMAP scan



Hello,

I am helping a small business owner to evaluate the quality of his IT setup. This company has one server which runs 
Windows Small Business Server 2003 R2 Premium Edition. This server hosts an Exchange instance which takes care of 
incoming and outgoing emails.

I ran an namp scan (nmap -T4 -A -v -PE -PA21,23,80,3389 <IP_address>) from a machine outside of the company network and 
got the results below. I am wondering why ports 80 and 443 are open since the server does not act as a web server. Also 
I am wondering if the Linksys router should be visible from the outside world ...

If anybody could comment on this and make suggestions on how to improve the security of that setup, I would appreciate 
it.

Cheers,
Dan.

Not shown: 990 closed ports
PORT     STATE    SERVICE      VERSION
25/tcp   filtered smtp
80/tcp   open     http         Microsoft IIS
|_ html-title: The page cannot be displayed
135/tcp  filtered msrpc
139/tcp  filtered netbios-ssn
143/tcp  open     imap         Microsoft Exchange Server 2003 imapd 6.5.7638.1
443/tcp  open     ssl/https?
|_ sslv2: server still supports SSLv2
|  html-title: Microsoft Outlook Web Access
|_ Requested resource was https://<...snipped...>
445/tcp  filtered microsoft-ds
993/tcp  open     ssl/imap     Microsoft Exchange Server 2003 imapd 6.5.7638.1
|_ sslv2: server still supports SSLv2
1723/tcp open     pptp         Microsoft (Firmware: 3790)
8081/tcp open     http         Linksys router http config (device model BEFSR41/BEFSR11/BEFSRU31)
|  http-auth: HTTP Service requires authentication
|_   Auth type: Basic, realm = Linksys BEFSR41/BEFSR11/BEFSRU31
|_ html-title: 401 Authorization Required



      

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