The kernel in Apple OS X before 10.10.5 does not properly mount HFS volumes, which allows local users to cause a denial of service via a crafted volume.
http://lists.apple.com/archives/security-announce/2015/Aug/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Sep/msg00001.html
http://lists.apple.com/archives/security-announce/2015/Sep/msg00005.html
http://www.securityfocus.com/bid/76340
http://www.securitytracker.com/id/1033276
https://support.apple.com/HT205212