Multiple vulnerabilities have been reported in Microsoft Silverlight, which can be exploited by malicious people to compromise a user's system.

1) Some errors exist when parsing TrueType fonts.

For more information see vulnerabilities #1 and #2:
SA49120

2) A double-free error when rendering XAML glyphs can be exploited via a specially crafted Silverlight application containing e.g. Unicode glyph characters for the Hebrew accent.

NOTE: This vulnerability affects Silverlight version 4.x only.

Successful exploitation of the vulnerabilities allows execution of arbitrary code.

Solution
Apply patches.
Further details available to Secunia VIM customers

Provided and/or discovered by
2) Alex Plaskett, MWR InfoSecurity

Changelog
Further details available to Secunia VIM customers

Original Advisory
MS12-034 (KB2681578, KB2690729, KB2636927):
http://technet.microsoft.com/en-us/security/bulletin/ms12-034

MWR InfoSecurity:
http://labs.mwrinfosecurity.com/advisories/2012/05/29/ms12-034---silverlight-hebrew-unicode-engine-glyph-rendering-heap-double-free/

Other references
Further details available to Secunia VIM customers

Deep Links
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