Multiple vulnerabilities have been reported in Microsoft .NET Framework, which can be exploited by malicious people to disclose potentially sensitive information, bypass certain security restrictions, and compromise a user's system.

1) An error within permissions checking of objects that perform reflection can be exploited via a specially crafted XAML Browser Application (XBAP) or an untrusted .NET application.

2) A sanitisation error when processing partially trusted code can be exploited to disclose certain data via a specially crafted XAML Browser Application (XBAP) or an untrusted .NET application.

3) The Entity Framework component loads certain libraries in an insecure manner, which can be exploited to load arbitrary libraries by tricking a user into opening certain files located on a remote WebDAV or SMB share.

4) A validation error when acquiring proxy settings via the Web Proxy Auto-Discovery (WPAD) can be exploited to execute JavaScript code with reduced restrictions.

5) An error within permissions checking of Windows Presentation Foundation (WPF) objects that perform reflection can be exploited via a specially crafted XAML Browser Application (XBAP) or an untrusted .NET application.

Solution
Apply patches.
Further details available to Secunia VIM customers

Provided and/or discovered by
1, 2, 4, 5) The vendor credits James Forshaw, Context Information Security.
3) Reported by the vendor.

Original Advisory
MS12-074 (KB2698035, KB2698023, KB2729450, KB2729449, KB2737019, KB2698032, KB2729453, KB2729460, KB2737083, KB2729452, KB2729462, KB2737084, KB2756872):
http://technet.microsoft.com/en-us/security/bulletin/ms12-074

Other references
Further details available to Secunia VIM customers

Deep Links
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