Severity Rating: Critical
Revision Note: V2.0 (May 11, 2012): Added an entry to the update FAQ to communicate that security update KB2656353 addresses the vulnerabilities described in this bulletin for all supported systems running Microsoft .NET Framework 1.1 Service Pack 1, except when installed on Windows Server 2003 Service Pack 2. There were no changes to the security update files. Customers who have successfully installed the update do not need to take any action.
Summary: This security update resolves two privately reported vulnerabilities in the .NET Framework. The vulnerabilities could allow remote code execution on a client system if a user views a specially crafted webpage using a web browser that can run XAML Browser Applications (XBAPs). Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
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