Word must be configured to warn when opening a document with custom XML markup.
An XCCDF Rule
Description
<VulnDiscussion>This policy setting specifies how Word behaves when opening a document that contains custom XML markup. Versions of Word that are distributed by Microsoft after January 10, 2010 no longer read the custom XML markup that may be contained within (.docx, .docm, .dotx, .dotm or .xml files. The new versions of Word 2007, Word 2010, and Word 2013 can still open these files, but any custom XML markup is removed. Configuring this setting will prompt the user with a warning, notifying of the lost of the XML markup. While this is the default setting, explicitly configuring the setting will ensure users are prompted.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility>System Administrator</Responsibility><Responsibility>Information Assurance Officer</Responsibility><IAControls></IAControls>
- ID
- SV-53598r1_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Set the policy value for User Configuration -> Administrative Templates -> Microsoft Word 2013 -> Word Options -> Advanced -> "Custom markup warning" to "Enabled: Prompt".