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IE: CHM Attacks are still alive (CHM attack without showHelp())
From: Arman Nayyeri <arman-n () Phreaker net>
Date: 2 Sep 2003 21:51:44 -0000

                              !! R/\/\an#0001 !!

CHM Attacks are still alive
Title:    CHM Attacks are still alive
Date:     Tuesday, September 02, 2003
Software: IE (What a nice program!!!)
Vendor:   Microsoft Corp. (I love Microsoft)
Patch:    N/A
Author:   Arman Nayyeri, arman-n () Phreaker net

Vendor Status:
Microsoft was not contacted, because I don't know email address of 


After releasing MS03-004 patch, it is still possible to execute a chm file 
without using of showHelp() command.
We can use mk:@MSITStore to execute CHM files, but with some tricks.

1.first we must have an help window opened in order to chm file to work 

2.We must open a window (or an iframe) that points to 

The first one is hard but easy with the help of the user.
We can say to user to press F1 key then by using a onkeydown event go to 
step 2.
As easy as this!!!!!
The microsoft patch just stop showHelp() functionality but it is still 
If you use a url for chm file ,it will open and show the content of file 
but do not execute programs without generating any errors. (I test it on 
one chm file ,you can try more, maybe its worked!)
But in the case of sandblad #11 ,I can't produce it without showHelp(), 
and I need the help of Andreas.
Andreas!, I believe that it will work, so try it!!.

As you can see, here is the simple javascript code that I write to exploit 
you must:
1.make a chm file and save it as c:\msit.chm (download free tool for 
making a chm file from http://go.microsoft.com/fwlink/?LinkId=14188 )
2.remove all ! from script
3.create a html file and copy the code into that
4.open the html page and press F1 key (at the top left corner of your 
(you may need to increase Timeout to allow the IE help to be opened)

-------------------------------BEGINING OF FILE---------------------------
<!h2>You should press "F1" key (at the top left corner of your keyboard)
function gotKey(){
if (event.keyCode==112){
        function () {
           document.write('<iframe id=I1 
src="mk:@MSITStore:c:\\msit.chm::/page.html"></'+'iframe><br><h3>I Love 
document.onkeydown = gotKey;
---------------------------------END OF FILE------------------------------

Arman Nayyeri is not responsible for the misuse of the information 
provided in this advisory. The opinions expressed are my own and not of 
any company. In no event shall the author be liable for any damages 
whatsoever arising out of or in connection with the use or spread of this 
advisory. Any use of the information is at the user's own risk.

Please Contact Me:
arman-n () Phreaker net

Arman Nayyeri 
        MCP, MCSE 2000(in next two weeks)


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