Vulnerability Note VU#939605

Microsoft COM

Microsoft COM is a technology that allows programmers to create reusable software components that can be incorporated into applications to extend their functionality. Microsoft COM includes COM+, Distributed COM (DCOM), and ActiveX Controls.

ActiveX controls

ActiveX controls are COM objects that are designed to be used in Internet Explorer. A web page can make use of an ActiveX control through the use of the OBJECT tag.

JVIEW Profiler

The JVIEW Profiler is a COM object provided by javaprxy.dll, which is an interface to the debugger in the Microsoft Java Virtual Machine.

The Problem

Internet Explorer will attempt to instantiate any COM object that is referenced by a web page. COM objects that are not ActiveX controls may cause unexpected results, such as crashing Internet Explorer. The JVIEW Profiler COM object crashes in a way that can be exploited to execute arbitrary code on a vulnerable system.

By convincing a user to view a specially crafted HTML document (e.g., a web page or an HTML email message), an attacker could execute arbitrary code with the privileges of the user. The attacker could also cause IE (or the program using the WebBrowser control) to crash.
Proof of concept code is publicly available.

Apply An Update
Apply the appropriate update, as specified in the Microsoft Security Bulletin. This update sets the "kill bit" for the JVIEW Profiler COM object.

Microsoft has listed several workarounds in the Microsoft Security Bulletin, including disabling ActiveX controls, disabling Active scripting, and unregistering javaprxy.dll.