The vulnerability is caused due to an error in the DHTML Edit ActiveX control when handling the "execScript()" function in certain situations. This can be exploited to execute arbitrary script code in a user's browser session in context of an arbitrary site.
Secunia has constructed a test, which can be used to check if your browser is affected by this issue:
[Only Registered and Activated Users Can See Links. Click Here To Register...]
The vulnerability has been confirmed on a fully patched system with Internet Explorer 6.0 and Microsoft Windows XP SP1/SP2.
Solution:
Set security level to high for the "Internet" zone (disable ActiveX support).
Also be sure to check in on windows update for the latest available updates for your operating system ..