Joomla! 3.9.21 Security Release announced
Joomla! 3.9.21 is a SECURITY FIX which addresses THREE vulnerabilities.
This release includes a Post Installation Message recommending that you edit your website's HTACCESS file.
See the Release Notes at the link below.
Core - XSS in mod_latestactions (affecting Joomla! 3.9.0 through 3.9.20).
Core - Open redirect in com_content vote feature (affecting Joomla! 3.0.0 through 3.9.20).
Core - Directory traversal in com_media (affecting Joomla! 2.5.0 through 3.9.20).
Back up before updating is highly recommended
Protect your assets.
Perform a FULL backup of your website (database and files) BEFORE updating the Joomla! CMS and/or its extensions.