This came out yesterday as an emergency patch for a vulnerability. I wouldn’t normally write about it here but, for some reason, they didn’t publish the list of changed files. So here they are:—
xmlrpc.php
wp-content\plugins\akismet.php
wp-admin\install-helper.php
wp-includes\version.php
wp-includes\gettext.php
wp-includes\pluggable.php
It is the first one that is important.