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 Firewalls
[Top] [All Lists]
<prev [Date] next>
[Advanced]
 <prev [Thread] next>

DoS problem.

from [Jorge Alfredo Garcia] Network Security [Permanent Link]
Subject: DoS problem.
Date: Fri, 20 Jan 2006 16:01:30 -0200 
I have two dedicated servers, both hosted by the same provider and
both on the same segmnet.
I am under a denial of services attack but idont know exactaly how to stop it.
Here is a piece of my netstat output:

tcp        0      1 XX.XX.XX.AA:47561           XX.XX.XX.BB:80        
     SYN_SENT
tcp        0      1 XX.XX.XX.AA:47562           XX.XX.XX.BB:80        
     SYN_SENT
tcp        0      1 XX.XX.XX.AA:47565           XX.XX.XX.BB:80        
     SYN_SENT
tcp        0      1 XX.XX.XX.AA:47564           XX.XX.XX.BB:80        
     SYN_SENT
tcp        0      1 XX.XX.XX.AA:47567           XX.XX.XX.BB:80        
     SYN_SENT

Ok, XX.XX.XX.AA is the server i am in now.
XX.XX.XX.BB is mine two and here are the connections:

tcp        0      0 XX.XX.XX.BB:80              XX.XX.XX.AA:50749     
     SYN_RECV
tcp        0      0 XX.XX.XX.BB:80              XX.XX.XX.AA:50598     
     SYN_RECV
tcp        0      0 XX.XX.XX.BB:80              XX.XX.XX.AA:50309     
     SYN_RECV

I have thousands of this connections on both servers.
I make iptables rules in both sites but the attack still running and
the rules dont work.

I cant understand how this attack can be made taking into account that
the attacker isnt inside any of my servers.
Why iptables rules dont work against this?

Thanx in advance.
[More with this subject...]




<Prev in Thread] Current Thread [Next in Thread>
Previous by Date:  RE: Firewall Dissertation, coder
Next by Date:  Re: DoS problem., Volker Tanger
Previous by Thread:  New Tool: Windows Permission Identifier v1.0, [at]
Next by Thread:  Re: DoS problem., Volker Tanger
Indexes:  [Date] [Thread] [Top] [All Lists]