Solved

NMAP Question

Posted on 2008-10-01
5
466 Views
Last Modified: 2013-12-04
Hola Experts,

I ran an Nmap scan from Nmap-Online.com and here are the results:

PORT STATE SERVICE
25/tcp open smtp
53/tcp open domain


Only thing is, checked my Pix Firewall and the Inbound acess-list only permits 25. I do not permit DNS into the network, so how is it finding this? and more importantly, how can I find it and shut it off?
0
Comment
Question by:jaysonfranklin
  • 2
  • 2
5 Comments
 
LVL 62

Expert Comment

by:gheist
ID: 22617432
It means your PIX is not protecting you. What will you do now?
0
 
LVL 1

Author Comment

by:jaysonfranklin
ID: 22617493
haha u funny.

seriously, if i telnet to port 53 from outside the pix, the port does not appear to be open. so, i was just wondering how the nmap-online found that it was open. it's just confusing since the pix is supposed to be stateful.
0
 
LVL 79

Accepted Solution

by:
lrmoore earned 500 total points
ID: 22618163
I believe it to be a false reading by nmap.
It shows mine to also have tcp/53 open and I know for a fact it is not.
Try another online scanner and you will get different results
http://labs.programming-designs.com/portscanner/
Or ShieldsUp at http://www.grc.com
0
 
LVL 1

Author Closing Comment

by:jaysonfranklin
ID: 31502060
thats what figured, i just wondered if somebody out there knew something i didn't. Thanks lrmoore.
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 22618498
Ya, even with an explicit deny acl there are no hits
access-list outside_access_in line 2 extended deny tcp any any eq domain (hitcnt=0)

Yet NMAP still shows it open
PORT STATE SERVICE
53/tcp open domain
80/tcp open http  

HTTP ain't open, either!

I can watch the live log and see the denies on other ports.
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Recently, I read that Microsoft has analysed statistics for their security intelligence report. It revealed: still, the clear majority of windows users do their daily work as administrator. An administrative account is a burden, security-wise. My ar…
Concerto Cloud Services, a provider of fully managed private, public and hybrid cloud solutions, announced today it was named to the 20 Coolest Cloud Infrastructure Vendors Of The 2017 Cloud  (http://www.concertocloud.com/about/in-the-news/2017/02/0…
Both in life and business – not all partnerships are created equal. As the demand for cloud services increases, so do the number of self-proclaimed cloud partners. Asking the right questions up front in the partnership, will enable both parties …
Both in life and business – not all partnerships are created equal. Spend 30 short minutes with us to learn:   • Key questions to ask when considering a partnership to accelerate your business into the cloud • Pitfalls and mistakes other partners…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question