Two vulnerabilities have been reported in Microsoft Windows, which can be exploited by malicious people to compromise a vulnerable system.

1) An integer underflow error when processing a Browser Election request can be exploited to cause a buffer overflow via an overly long Server Name string sent in a specially crafted packet.

Successful exploitation of this vulnerability may allow execution of arbitrary code, but requires the target system to be a Master Browser.

2) A validation error when processing Server Message Block (SMB) responses can be exploited by sending a specially crafted response to a client-initiated SMB request.

Successful exploitation of this vulnerability allows execution of arbitrary code, but requires tricking a user into connecting to a malicious SMB server (e.g. via a link hosted on a web page).

Solution
Apply patches.
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Provided and/or discovered by
1) Cupidon-3005
2) Reported by the vendor.

Changelog
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Original Advisory
MS11-019 (KB2511455):
http://www.microsoft.com/technet/security/Bulletin/MS11-019.mspx

Cupidon-3005:
http://archives.neohapsis.com/archives/fulldisclosure/2011-02/0284.html

Other references
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Technical Analysis
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Deep Links
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