Security updates for Internet Explorer 7 Beta 1 and Internet Explorer in Windows Vista Beta 1 are now available from the Windows Vista/IE 7 beta downloads page on the Connect site. Direct links to these updates are also provided below. These security updates resolve a vulnerability in IE 7 Beta 1 and IE in Windows Vista Beta 1 that has already been addressed for released/supported versions of Internet Explorer by Microsoft Security Bulletin MS05-052.
These security updates apply only to the official Internet Explorer 7 Beta 1 and Windows Vista Beta 1 builds (build version 5112 for each). You do not need to install this update if you have already installed one of the more recent Windows Vista builds that are available from the Windows Vista/IE 7 beta downloads page on the Connect site (the latest is build 5231). More specific details on the issue and fix, as well as detailed installation instructions, can be found in the release notes that are included in the downloads for these security updates.
Note: Both updates requre you to be an official tester with access to connect.microsoft.com.