Microsoft Office 2003 SP3 and 2007 SP3, Word 2003 SP3 and 2007 SP3, and Word Viewer allow remote attackers to read arbitrary files via an XML document containing an external entity declaration in conjunction with an entity reference, related to an XML External Entity (XXE) issue, aka "XML External Entities Resolution Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A18819
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2013/ms13-072