Microsoft Excel 2002 SP3 and 2003 SP3, and Office 2004 for Mac, does not properly validate binary file-format information, which allows remote attackers to execute arbitrary code via a crafted Excel document, aka "Negative Future Function Vulnerability."
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.