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

1) An error in the parsing of records can be exploited to corrupt memory via a specially crafted file.

2) An error in the parsing of sheet object types can be exploited to corrupt memory via a specially crafted file.

3) An error in the parsing of MDXTUPLE records can be exploited to cause a heap-based buffer overflow via a specially crafted file.

4) An error in the parsing of MDXSET records can be exploited to cause a heap-based buffer overflow via a specially crafted file.

5) An error in the parsing of FNGROUPNAME records may result in the use of uninitialised memory via a specially crafted file.

6) An error in the parsing of a ZIP header within XLSX files when decompressing certain XML elements may result in use of uninitialised memory.

7) An error in the parsing of DbOrParamQry records can be exploited to corrupt memory via a specially crafted file.

Successful exploitation of the vulnerabilities may allow execution of arbitrary code.

Solution
Apply patches.
Further details available to Secunia VIM customers

Provided and/or discovered by
1) The vendor credits Nicolas Joly, Vupen.
2-5) Sean Larsson, VeriSign iDefense Labs.
6) An anonymous person via ZDI.
7) The vendor credits Damián Frizza, Core Security Technologies.

Changelog
Further details available to Secunia VIM customers

Original Advisory
MS10-017 (KB980150, KB978471, KB978474, KB978382, KB980837, KB980839, KB980840, KB978383, KB978380, KB979439):
http://www.microsoft.com/technet/security/bulletin/ms10-017.mspx

iDefense Labs:
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=859
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=860
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=861
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=862

ZDI:
http://www.zerodayinitiative.com/advisories/ZDI-10-025/

Core Security:
http://www.coresecurity.com/content/CORE-2009-1103

Deep Links
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