Messaging Gateway identifies Visio .vsdx files as archives rather than Microsoft Office documents

Products

• Messaging Gateway

Issue/Introduction

Symantec Messaging Gateway (SMG) identifies Visio .vsdx files as archives rather than as Microsoft Office 2013 documents. 

Cause

This is technically correct as .vsdx documents are structured as zip archives which is detected by SMG when analyzing the file structure and contents.

 

Reference:

https://msdn.microsoft.com/en-us/library/office/jj228622.aspx

"The Visio 2013 file format uses the Open Packing Conventions (OPC), which defines a structured means to store application data together with related resources using a container of some sort─for example, a ZIP file. At a basic level, a Visio 2013 file is really a ZIP container that contains other types of files. In fact, you can save a drawing in Visio 2013 as a .vsdx file, rename the file extension to "*.zip" in Windows Explorer, and then open the file like a folder to see the contents inside."

Resolution

This issue has been addressed with the SMG 10.6.3 release.

How to detect .vsdx files as Microsoft Office 2013 document:

Policies can be written to identify Visio (.vsdx) documents by creating an attachment list based on the .vsdx attatchment via the Content -> Resources -> Attachment Lists page and then implementing that list with the following policy logic:

If the attachment or body part is in the attachment list "Archive Files (default)"
AND
If the attachment or body part is in the attachment list "Visio Files"

Where "Visio Files" is the name of the attachment list created for the .vsdx file extension.