This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Office Word. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within how the application parses a PAPX FKP sections. When parsing a PAPX FKP section, the application will store a calculation. However, when repairing a damaged document, the application will explicitly trust this calculation in a loop that is used to index into an array of objects. This will allow for an out-of-bounds access of an object which can lead to code execution under the context of the application.