In WordPress before 4.7.3, there is cross-site request forgery (CSRF) in Press This (wp-admin/includes/class-wp-press-this.php), leading to excessive use of server resources. The CSRF can trigger an outbound HTTP request for a large file that is then parsed by Press This.
https://wpvulndb.com/vulnerabilities/8770
https://wordpress.org/news/2017/03/wordpress-4-7-3-security-and-maintenance-release/
https://github.com/WordPress/WordPress/commit/263831a72d08556bc2f3a328673d95301a152829
https://codex.wordpress.org/Version_4.7.3
http://www.securitytracker.com/id/1037959