Microsoft Office documents (.doc) may contain hidden data, or meta-data, that includes user information, such as the user’s name and initials, company name, the name of the computer, the path to the location where the document was saved, the names of previous document authors, hidden text or cells, comments, and other information about the document itself. The document owner may not be, and usually isn’t, aware that the electronic form of the document contains anything more than what he/she has written and can see on the computer screen. This could lead to the inadvertent disclosure of sensitive or proprietary data when the electronic versions of these documents are shared with others.
Doc Scrubber is a free application from JavaCool Software that lets you “scrub” word documents for data such as the user name of the document creator, the date and time of creation, the name of other users who edited the document, time of editing and more. Doc Scrubber supports Word documents in the classic .DOC format (the default format in Word 97, 2000, XP, 2003).
The value of this is that you can verify that the alleged writer of a document actually is the sender, and you can check to see if other people were involved in the production of the document. In rare cases, you can get an indication of the writers sentiment about the topic, if for example the original file location path contains an expressive folder name.
There are famous true cases where foul play has been revealed by reviewing word document metadata. Read more in this article (from 2006): http://news.cnet.com/Editing-tips-from-the-NSA/2100-1029_3-6030745.html
This whitepaper from SANS Institute (SANS.org) by Larry Pesce gives good information on metadata in several different kinds of electronic files as a source of information:
“This paper will illustrate ways in which metadata stored in common types of documents can reveal secrets about an organization”
http://www.sans.org/reading_room/whitepapers/privacy/document-metadata-silent-killer_32974
(NOTE: The above link leads to a file that you must save to disk. Then, add the file extention .pdf and you can open it with your PDF-reader software).
Related previous posts on iOSINT:
https://iosint.wordpress.com/2010/03/31/an-image-file-says-more-than-a-picture/