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 when validating certain data within Excel files can be exploited to corrupt memory.

2) An error when handling the OBJECTLINK record within Excel files can be exploited to corrupt memory.

3) An error when validating certain data within Excel files can be exploited to corrupt memory.

4) An error when handling the SXLI record within Excel files can be exploited to corrupt memory.

5) An error when handling the MergeCells record within Excel files can be exploited to cause a heap-based buffer overflow.

6) A type mismatch error when handling the Series record within Excel files can be exploited to cause a heap-based buffer overflow.

Successful exploitation of the vulnerabilities allows execution of arbitrary code, but requires tricking a user into opening a malicious file.

Solution
Apply patches.
Further details available to Secunia VIM customers

Provided and/or discovered by
3) Reported by the vendor.
6) An anonymous person via ZDI

The vendor also credits:
1, 2) Omair
4) Omair via iDefense
5, 6) Sean Larsson and Jun Mao via iDefense

Changelog
Further details available to Secunia VIM customers

Original Advisory
MS12-030 (KB2553371, KB2596842, KB2597086, KB2597161, KB2597162, KB2597166, KB2597969, KB2665346, KB2665351):
http://technet.microsoft.com/en-us/security/bulletin/ms12-030

ZDI:
http://www.zerodayinitiative.com/advisories/ZDI-12-157/

Alternate/detailed remediation
Further details available in Customer Area

Deep Links
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