Yet another baseless sensational headline. Just because something is not on the latest release doesn't make it insecure, and for sure no one claimed that that was the way the documents were retrieved.

Anyway, following the logic of the title, I can have a better sensationalist head line - "In 3 months 80% of wordpress sites will be insecure" (in 3 months version 5.5 of PHP will be EOL, and only about 16% of wordpress sites use a more current one). BTW currently it is more then 50% which are not secure.