The Microsoft virtual machine (Microsoft VM) includes a security vulnerability that may allow script code in a Web page or HTML-based e-mail message access to ActiveX controls that should not be available in those contexts. This vulnerability can give malicious script code access to any ActiveX controls that are installed on the visiting user's computer. The ActiveX controls could then give the malicious script complete control over the visiting user's computer, including the ability to read and write files on the local hard drive.
This affects the following builds of the Microsoft VM:
All builds in the 2000 series.
All builds in the 3100 series.
All builds in the 3200 series.
All builds in the 3300 series.
The vulnerability is caused by a flaw in a security check that is intended to prevent the com.ms.activeX.ActiveXComponent system class from being used as an applet. This system class, which is provided with the Microsoft VM, is intended for use only in applications or by signed and trusted applets.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
For more information, please see Microsoft Security Bulletin MS00-075 at the following Microsoft Web site: