Safari in Apple OS X before 10.10 allows remote attackers to cause a denial of service (universal Push Notification outage) via a web site that triggers an uncaught SafariNotificationAgent exception by providing a crafted Push Notification.
https://support.apple.com/kb/HT6535
https://exchange.xforce.ibmcloud.com/vulnerabilities/97625
http://www.securitytracker.com/id/1031063
http://www.securityfocus.com/bid/70629
http://archives.neohapsis.com/archives/bugtraq/2014-10/0101.html