Cross-site request forgery (CSRF) vulnerability in wp-admin/post.php in WordPress before 4.2.4 allows remote attackers to hijack the authentication of administrators for requests that lock a post, and consequently cause a denial of service (editing blockage), via a get-post-lock action.
https://wordpress.org/news/2015/08/wordpress-4-2-4-security-and-maintenance-release/
https://core.trac.wordpress.org/changeset/33543
https://core.trac.wordpress.org/changeset/33542
https://codex.wordpress.org/Version_4.2.4
http://www.securitytracker.com/id/1033178
http://www.securityfocus.com/bid/76160
http://www.debian.org/security/2015/dsa-3383