Re: Server blocks access of IP after nmap scan

[Martin Schneider <nighthawk2600 () gmail com>]

On 05/18/2011 10:34 AM, Dan Lynch wrote:
> > so i guess after the nmap scan the server somehow
> > protected itself by blocking access to the site for my ip. I
> > would like to know what I can do in this case, how I can
> > successfully complete a nmap scan without putting it 'down'.
> First make sure this is within the acceptable use guidelines of your ISP and the server owner's ISP. If it's not, you'd 
> best knock it off.
>
> But if it is, there's likely an active IPS somewhere in your path to the server. Use nmap's timing options (either -T or -max-rate)to 
> go "low-and-slow" and avoid triggering the IPS. You don't know what the IPS thresholds are set to, so be conservative, and be 
> patient -- this will take a while.
>
> An idle/zombie scan is inherently slower, but still subject to rate-based IPS alerts. You protect your real IP address 
> from the target, but the zombie will get blocked if it triggers the IPS.
>
>
> Dan Lynch, CISSP
> Information Technology Analyst
> County of Placer
> Auburn, CA
> ------------------------------------------------------------------------
> Securing Apache Web Server with thawte Digital Certificate
> In this guide we examine the importance of Apache-SSL and who needs an SSL certificate.  We look at how SSL works, how 
> it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, 
> install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are 
> highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates.
>
> http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1
> ------------------------------------------------------------------------
okay you have to understand firewalls here.. by port scanning his server 
your connecting at a very high rate. More than likely you are being 
blocked at because of these high rate connections to his server. I like 
what Dan Lynch said about using the max-rate going slow and using nmaps 
timing options. If you are connecting slower than 5 connects a minute 
you may not be blocked. However, a scan could generate 100s of 
connections/half connects depending on the scan a minute which is why 
you are blocked out. Try to also generate different information with 
traceroute or hping2 which i saw that was already suggested which is a 
good idea.

using traceroute could locate you to the firewall but more than likely  
it will be blocked by the firewall so you may have to use different 
packet sending options to generate different results.

All right everyone i bid you good day.

------------------------------------------------------------------------
Securing Apache Web Server with thawte Digital Certificate
In this guide we examine the importance of Apache-SSL and who needs an SSL certificate.  We look at how SSL works, how 
it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, 
install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are 
highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates.

http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1
------------------------------------------------------------------------