One reason this WordPress update happened is because of a cross-site scripting (XSS) vulnerability in MediaElement. The records have since been removed and MediaElement have released an update settling the bug. What’s more, there is also a plugin with fixed files available.
21 other bugs were fixed in the new update. Some of which are listed below:
- JavaScript errors that prevented saving posts in Firefox have been fixed.
- The previous taxonomy-agnostic behavior of get_category_link() and category_description() was restored.
- Switching themes will now attempt to restore previous widget assignments, even when there are no sidebars to map.
Click here for more information about all the issues fixed in WordPress 4.9.2.
Download WordPress 4.9.2 Security and Maintenance Release or venture over to Dashboard → Updates and click “Update Now.”
Websites that support automatic background updates are already beginning to update to WordPress 4.9.2.