alt Hacker NewsTo respond to Grandfather comment, modern Office files are really just ZIPs with different extensions, they even have the magic string "PK" at the very beginning of the file.
I do wonder, since a lot of tools outside of the MS ecosystem can read Office files (e.g. LibreOffice and Google Docs as well as plenty of other online tools), if indeed the hack as described by the article is possible. One would just need to figure out the ZIP stacks used by said tools.
You can even just rename a docx file to use the zip extension and then manually unzip it for those curious. If I remember correctly, the contents are XML files with structure encoding the formatting around the content.