Office files… have been the major loophole exploited by malicious hackers to inject malformed data such as malformed data to spread malware.

Office File Validation add-in is available for free download from Microsoft Download Center, or directly download with the link below. Note that there are several prerequisite architecture updates to Microsoft Word and Microsoft Publisher before you can install Office File Validation as specified in KB2501584, which should have delivered automatically via Microsoft (Windows) Update.
Microsoft Office File Validation Add-in (KB2501584): SFV.exe

From:
Microsoft Office File Validation Add-in Free Download � My Digital Life