Joomla! 3.6.4 is now available. This is a security release for the 3.x series of Joomla! which addresses two critical security vulnerabilities and a bug fix for two-factor authentication. We strongly recommend that you update your sites immediately.
This release only contains the security fixes and bug fix; no other changes have been made compared to the Joomla! 3.6.3 release.
https://www.joomla.org/announcements/release-news/5678-joomla-3-6-4-released.html