Microsoft Document Inspector Sniffs Out Hidden Data in Office Files

New tools for Excel, PowerPoint and Word lower the risk that users share more than they bargained for.

Microsoft Document Inspector

Office files are a trove of metadata and other hidden information. If not managed properly, they can reveal more about an organization than users intend, potentially landing them in hot water.

In updates for Office 2013 and 2010, Microsoft has added new tools to the Document Inspector feature in Excel, PowerPoint and Word, announced Steve Kraynak, a Microsoft Office program manager. Document Inspector enables Office users to prepare "documents, presentations, or workbooks for publishing and sharing by checking for items that may contain hidden or private information," he explained in a Dec. 9 blog post.

"In some cases, it will remove such items from your document; in other cases, it alerts you even if it can't automatically remove the items," continued Kraynak.

With the addition of several new inspection modules, users can now uncover embedded documents, macros, forms and ActiveX controls in Excel, PowerPoint and Word Files. Excel users also gain the ability to detect a lengthy list of document attributes, including links to other files, PivotTables, PivotCharts, cube formulas, slicers and timelines (Excel 2013), to name a few.

It's worth poking around using Document Inspector, according to Kraynak. "Macros (VBA Code), forms, and ActiveX Controls may contain personal or private information that is not readily visible in your document, but someone who goes looking would be able to find it," Kraynak wrote.

Similarly, Excel's active filters may give away too much information. "When you use filters in your workbook, the filter conditions are cached in the workbook, even if you delete the rows that contain those values," explained Kraynak. For instance, if a filter condition is set to contain "secret," "you may still see the word 'secret' if you look at the filter condition" even if all the rows are deleted.

While the new features shed some much-needed light on hidden data, it's no substitute for good practices, Kraynak wrote.

Users "should keep in mind that there are items that the Document Inspector is not designed to detect," he said. "For example, in Excel, you can put data in a far off row or column that you might not see when casually reviewing the spreadsheet, or in Word or PowerPoint, you could cover some data with a picture and forget it's there."

Nor should the tool be used to take shortcuts during the content creation and management process, he added. "It's important to remember that the Document Inspector is not designed to take the place of common workflow processes, such as technical and legal review, peer review and editorial review."

Lastly, Document Inspector isn't meant to act as a converter for WYSIWYG (what you see is what you get) file types. "For example, you might want to save your document in one of the paper-like formats for sharing, such as Open XML Paper Specification (OpenXPS) or the Portable Document Format (PDF), or as a Single-File Web Page document (MHT)," he said.

Pedro Hernandez

Pedro Hernandez

Pedro Hernandez is a contributor to eWEEK and the IT Business Edge Network, the network for technology professionals. Previously, he served as a managing editor for the network of...