Vulnerability Note VU#140898

Microsoft Java implementation allows execution of malicious code

The VM includes a class named "com.ms.osp.ospmrshl" that provides XML support to Java applets. This class exposes certain methods that are only intended to be accessed by trusted applets. However, the class does not check whether the applet is trusted before exposing these methods. Therefore, untrusted applets may access the methods and use them to execute arbitrary code on the client system.

The default configuration of Outlook Express 2002 and Outlook Express 6 opens HTML messages in the Restricted Sites zone, where Java applets are disabled. The same is true for Outlook Express 98 and 2000 if the Outlook Email Security Update has been applied. In these cases, the vulnerability described herein is not exploitable within Outlook Express.

This vulnerability may still be exploited by leading an Internet Explorer user to visit a web page containing a malicious Java applet.

II. Impact

For more information, see:

http://www.microsoft.com/technet/security/bulletin/MS02-052.asp

Systems Affected

http://www.securityfocus.com/bid/5670
http://www.microsoft.com/technet/security/bulletin/MS02-052.asp

Credit

Thanks to Jouko Pynnonen for reporting this vulnerability.

This document was written by Shawn Van Ittersum.

Other Information

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