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

1) A boundary error when handling malformed BIFF records can be exploited to cause a stack-based buffer overflow via a malicious file containing a specially crafted Named Graph record.

2) An error when handling set font values within Excel files can be exploited to corrupt memory via a malicious file containing a specially crafted set font value.

3) An input validation error when handling filter records can be exploited to corrupt memory via a specially crafted file.

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
1) Discovered by Manuel Santamarina Suarez and reported via ZDI.
2) Reported by the vendor.
3) Greg MacManus, iDefense Labs.

Changelog
Further details available to Secunia VIM customers

Original Advisory
MS07-023 (934233):
http://www.microsoft.com/technet/security/Bulletin/MS07-023.mspx

ZDI:
http://www.zerodayinitiative.com/advisories/ZDI-07-026.html

iDefense Labs:
http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=527

Other references
Further details available to Secunia VIM customers

Deep Links
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