On April 23, 2015, WordPress 4.0.3 was released to the public. This is a maintenance update for WordPress 4.0.2.
To download WordPress 4.0.3, update automatically from the Dashboard > Updates menu in your site's admin area or visit https://wordpress.org/download/release-archive/.
For step-by-step instructions on installing and updating WordPress:
If you are new to WordPress, we recommend that you begin with the following:
Fix database writes for esoteric character sets, broken in the WordPress 4.0.2 security release. Neither UTF-8 nor latin1 were affected. For more information, see ticket #32051.
readme.html wp-admin/about.php wp-includes/version.php wp-includes/wp-db.php