RE: Detailed analysis: Buffer overflow in Explorer.exe on Windows XP SP1

["Executable Security" <exurity () rogers com>]

Hi:

> -----Original Message-----
> From: nesumin [mailto:nesumin () softhome net]

> I could create the exploit code on my Japanese Windows XP SP1.
> Perhaps, I think you can easily create the full exploit code
> by the following;
>
> * You can directly specify all overwritten data without thinking
>   the UNICODE conversion if you create the "desktop.ini" as "UTF-16".
>   (Adding BOM and encoding "[.ShellClassInfo]\x0d\x0a".)
>
> * You can get the code area of about 0xFF4 bytes.
>   (Before and after RET address)

Obviously, I was playing in the ANSI world. Yes, I agree with you that the
exploit code written in RTF-16 can be created with a size of about 0xFF4
bytes. A piece of 0xFF4 bytes long exploit code can do a lot. So, my
previous statement about limited exploitation of this buffer overflow is not
accurate.

It should be very easy to fix this bug. I manually modified the 800H to 400h
in shell32.dll to fix it.

Thanks a lot for your mention of BOM and UTF-16. Your concept is learnt and
programmatically reproduced with GetPrivateProfileSectionW.

Best regards

Peter Huang