This indicates an attack attempt to exploit an Information Disclosure Vulnerability in Microsoft Office.
A remote attacker could exploit this vulnerability by enticing a user to open a maliciously crafted document and clicking a malicious MACROBUTTON field. Successful exploitation would allow for the disclosure of an arbitrary file.
Microsoft Office 2010 Service Pack 2
Microsoft Office 2013 RT Service Pack 1
Microsoft Office 2013 Service Pack 1
Microsoft Office 2016
Microsoft Office 2019
Microsoft Office 365 ProPlus
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems.
Apply the most recent upgrade or patch from the vendor.