WordPress versions 4.8.2 and earlier are affected by an issue where
$wpdb->prepare() can create unexpected and unsafe queries leading to potential SQL injection (SQLi). WordPress core is not directly vulnerable to this issue, but we’ve added hardening to prevent plugins and themes from accidentally causing a vulnerability. Reported by Anthony Ferrara.
This release includes a change in behaviour for the
esc_sql() function. Most developers will not be affected by this change, you can read more details in the developer note.
Thank you to the reporter of this issue for practicing responsible disclosure.
Download WordPress 4.8.3 or venture over to Dashboard → Updates and simply click “Update Now.” Sites that support automatic background updates are already beginning to update to WordPress 4.8.3.