vbdec remote scripting

Author: David Zimmer
Date: 11.19.22 - 1:42pm

Cool new feature in vbdec came out today.

If you go to options and click Allow Remote Scripting you can now interact it with from external scripting clients that support GetObject().

This can include python with the win32com.client package.

While VB6 does support building ActiveX executables, I kind of hate them and never use them. That would be the traditional way to go about it. I had remembered seeing some code on vbforums.com from user wqweto about how to register a standard vb form in the Running Object Table (ROT). This however did not seem to work with classes in standard vb6 executables.

I compared the Object.ObjectType flags of classes between ActiveX exe classes and standard classes and noticed that bit 0x800 was not set in standard ones.

Modifying the flags on disk and classes now worked through the ROT. Sweet. I then whipped up a small test to patch the objType in memory to see if it could be modified on the fly. No go! BUT! Then I realized the class had already been created before I patched the flags. Reinstanting the class, takes on the new flags and voila now they are all accessible!

I have now released a class which will patch all the classes in the object table and allow you to add elements to the ROT.

Seems to be working great so far. Python and VBS remote examples have been added to the /Scripts directory in the vbdec installer.

Being familiar with the vb internals has some french benefits.

In other news, vbdec got an Analyze Object Types form which breaks down the bit fields and allows you to easily set and patch the values in a binary. This will let us easily experiment with them.

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