https://wordpress.org/news/2017/09/wordpress-4-8-2-security-and-maintenance-release/
WordPress 4.8.2 is now available. This is a security release for all previous versions and we strongly encourage you to update your sites immediately.
WordPress versions 4.8.1 and earlier are affected by these security issues:
$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
Source: Security Feed