wp-includes/class-phpass.php in WordPress before 3.7.5, 3.8.x before 3.8.5, 3.9.x before 3.9.3, and 4.x before 4.0.1 allows remote attackers to cause a denial of service (CPU consumption) via a long password that is improperly handled during hashing, a similar issue to CVE-2014-9016.
https://wordpress.org/news/2014/11/wordpress-4-0-1/
http://www.securitytracker.com/id/1031243
http://www.mandriva.com/security/advisories?name=MDVSA-2014:233
http://www.debian.org/security/2014/dsa-3085
http://openwall.com/lists/oss-security/2014/11/25/12