WordPress 4.5.2 is now available for download and is a security release for all previous versions. It is highly recommended that you update your sites immediately.
More information on the update is available: https://wordpress.org/news/2016/05/wordpress-4-5-2/
If you have not done so already – download the update or simply use your existing installation of WordPress to update your site. Either way – this is an excellent time to make a backup copy of your site(s) before upgrading.