Unpacking Yodas Protector 1.03.3

Agustus 15, 2010 — richardyusan

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C:\Yodas Protector Unpacking.swf
Build 2 successfully completed
Created at: Sat Aug 14 08:28:53 2010
Flash player required: v6.0 or above
Size: 1654 KB
Total frames in main movie: 5160
Playback frame rate: 20
Approximate playback time: 258 seconds

Annotated text transcript:

Unpacking Yoda's Protector 1.03.3
Tools :

-OllyDBG
-OllyDump
-IsDebugPresent (If you need)
-LordPE
-TargetFile

This Tutorial is writen by Richard Irfan Yusan

richardyusan@rocketmail.com
The TargetFile 
yoda's Protector 1.03.3 -> Ashkbiz Danehkar
Entryopy : PACKED
EP Check : PACKED
Load the target file to OllyDBG
Set your Exceptions Settings like this
make sure this checkbox is checked
If User32.dll already loaded into memory, set your ollydbg events setting back to normal
Uncheck !
Right Click > Go To > Expression

Or

CTRL + G
Type "BlockInput"
Fill with NOPs
Place Breakpoint here
F2
Now, we must fix IsDebuggerPresent

there are two method :

1.Manual Fix : Continue watching
2. Using IsDebuggerPresent OllyDBG plugin , you can skip this step
MOV EAX,0
GetCurrentProcessId

Case sensitive
Yoda uses CreateToolhelp32Snapshot to retrieve all running processes. Then , yoda search for process that started unpackme and it checks does that proces has same PID as unpackme itself. If not, yoda terminates that process which is OllyDbg.exe in our case. If we patch CreateToolhelp32Snapshot API, we will get Invalid_Handle exception. But there is another very easy way how to trick yoda. Yoda uses GetCurrentProcessId API to retrieve it's own PID. We can make yoda think that it is ollydbg.exe if we set that API to retireve olly's PID. How we can do that? By injecting simple patch.
00000730 is OllyDBG PID
730 mean ollydbg pid
Run Debugged Program

F9
We land at this breakpoint 
Run Debugged Program Again

F9
Set Memory BP on access
OEP
CTRL+A to analyze this code
UnPackMe file run without error 
 
Entropy : NOT PACKED
EPCheck : NOT PACKED
And UnPackMe Unpacked succesfully ! 

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