Microsoft MCWNDX.OCX ActiveX buffer overflow

PROGRAM: MICROSOFT MCIWNDX.OCX ACTIVEX BUFFER OVERFLOW
HOMEPAGE: www.microsoft.com
VULNERABLE VERSIONS: MCWNDX is an ActiveX shipped with Visual Studio 6 to
support multimedia programming.

DESCRIPTION

MCWNDX is an activeX shipped with Visual Studio 6 to
support multimedia programming. Although not many people use it anymore,
however it still can be called through CLSID in a website and passing a
large amount of data to the activex will cause an buffer overflow.

Since this Activex is only shipped with VIsual Studio 6.0, so only
people who are having Visual Studio 6.0 will be affected or people
who are still using old multimedia programs coded in Visual Studio 6.0
(In my PC, the last date the ActiveX is patched is in 1996 ! I am using
VS Sp 4)

DETAILS

The ActiveX has a property called "Filename" which is used to specify
the .mci file to load. However if it is passed with a very large
string(640KB
is good enough :-) ), it will cause a bufferoverflow. (I can't overwrite the
EIP using this overflow in my XP, however it doesn't mean the problem can't
be exploited)

Microsoft has been noticed but since the hole is maybe minor to them so
they don't response to me even a short sentence like "Thank you !"

WORKAROUND

Delete the file MCWNDX.ocx in your SYSTEM32 directory if you are
using 2000 or XP or in your SYSTEM directory if you are using WIN ME or
below

CREDITS

Discovered by Tri Huynh from Sentry Union

DISLAIMER

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