Beware unknown Excel spreadsheets

Microsoft has announced that there is, unfortunately, another currently unpatched exploit in Excel.

In its security bulletin, Microsoft warned that “other Office applications are potentially vulnerable” to the zero-day flaw.

Zero-day refers to a flaw for which there is an exploit but no available fix. The Excel vulnerability is Microsoft’s fifth zero-day exploit since December, and part of an increasingly troubling trend.

The zero-day flaw affects Office versions 2000, XP, 2003 and 2004 for the Mac, but not 2007 or Works 2004, 2005 or 2006.

That means don’t open any Excel spreadsheets that you don’t know and trust the source if you are using any of the vulnerable versions.  In related news – if you aren’t already aware, there is a similarly troublesome exploit available for Microsoft Word.  While it is fun to pick on Microsoft, note that this problem is a nearly unavoidable result of increasingly complex software.  Even some of the best known security software and networking tools have had security vulnerabilities in the past.

[tags]Exploit out for Excel, Microsoft Word vulnerability, Secure software is tough – just ask Microsoft (and others)[/tags]