Some versions of the Microsoft virtual machine (Microsoft VM) contain a flaw that could allow untrusted Java applets from an attacker's site to be run instead of the trusted applet from the intended site.
The Microsoft virtual machine (Microsoft VM) enables Java programs to run on Windows platforms. The Microsoft VM is included in most versions of Windows and Internet Explorer.
The Microsoft VM contains a flaw that incorrectly parses URLs if they contain a colon used to indicate the port number. The vulnerability results because it's possible to create a URL that will cause the Microsoft VM to incorrectly determine the domain from which a Java applet was loaded, and conclude that it came from one web site when in fact it came from another. Specifically, if a URL is crafted in a particular format containing references to two different web sites, the VM will incorrectly process it and load a Java applet from an untrusted site while running it in the trusted site's domain.
Because the malicious applet would be located in the context of the legitimate site's domain, it could potentially access any cookies that the legitimate site had placed on the victim user's system. Additionally, any information the malicious applet solicited from the user could be relayed back to the attacker's site instead of the intended site.
Apply a patch from the vendor
Thanks to Jouko Pynnonen for reporting this vulnerability.
This document was written by Chad R Dougherty.
|Date First Published:||2003-01-21|
|Date Last Updated:||2003-01-21 21:56 UTC|