Improper Input Validation
Microsoft Excel 2000, 2002, 2003, Viewer 2003, Office 2004 for Mac, and Office v.X for Mac does not properly handle certain opcodes, which allows user-assisted remote attackers to execute arbitrary code via a crafted XLS file, which results in an "Improper Memory Access Vulnerability." NOTE: an early disclosure of this issue used CVE-2006-3432, but only CVE-2007-0028 should be used.
CWE-20 - 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.