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Re: Smurf ,land attacks
From: j mattox <security () wirerats org>
Date: 12 Nov 2002 11:50:51 -0000

In-Reply-To: <001c01c2882c$53eec250$0f64640a () packeteye com>

I believe that this can be done with tools such as dsniff.  In = 
addition, any 
attack which uses ICMP protocol can easily be spoofed simply by writing = 
small script.  For example, using ping alone you can do the following = 
using the dummy module for linux: 

/sbin/insmod -o dummy /lib/modules/[kernel 

/sbin/ifconfig dummy up ( or any address) 

ping -I [hostname to send packets to] -P [packetsize] 

It will send a custom packetsize to the specified hostname.  Keep in = 
this is strictly for ICMP traffic. 

Hope this helps! 

Wirerats Network Security, Inc. 

My question is this: how does an attacker accomplish modifying a packet 
sending it; such as in a land.c attack - how does he modify the packet to
reflect the victim's source and destination IP and then send it onto the

-----Original Message-----
From: Fuchs Bernhard [mailto:Bernhard.Fuchs () itellium com]
Sent: Tuesday, November 05, 2002 5:58 AM
To: 'vijay vikram shreenivos'; security-basics () securityfocus com
Subject: AW: Smurf ,land attacks

Hi there!

with "IP spoofing" you give a different source address to the packet. the
address is different to your real address. You do this for cloaking your
scan or if company A scans company B and spoofes the address of company 
so company b thinks it is company c scanning them! o.k.? but company a 
not get any results back! this is mostly to cloak your own scan.

Smurf is a DoS-Attack (denial of service)
You Amplifi your ping through a big network. You ping a subnet like
x.x.x.255 with an SPOOFED IP-Adress and every computer on that big net
responses to the poor little machine  that has the IP-Adress. Think of 
B subnet with a few hosts reply to a ADSL connected machine... 1500kb
download and 196 kb upload :-)

land attack is a TCP SYN packet that has the ip address and port number 
the source set to the same as the ip address and port number for the
destination. the server connects to itself.

any comments?

by the way, google knows it too :-)

Mit freundlichen Grüßen/ sincerely yours

Bernhard Fuchs
Junior System-Engineer

Systems & Services GmbH
Fürther Straße 205
90429 Nürnberg

Tel.:   +49-911-14-27321
Fax:    +49-911-14-22016
mailto:bernhard.fuchs () itellium com

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-----Ursprüngliche Nachricht-----
Von: vijay vikram shreenivos [mailto:karpagamekapali () rediffmail com]
Gesendet: Samstag, 2. November 2002 08:15
An: security-basics () securityfocus com
Betreff: Smurf ,land attacks

Hi list,

Can someone give the EXACT differences btw

and IP soofing attacks.

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