Race condition in runner in Install.framework in the Install Framework Legacy component in Apple OS X before 10.10.5 allows attackers to execute arbitrary code in a privileged context via a crafted app that leverages incorrect privilege dropping associated with a locking error.
http://lists.apple.com/archives/security-announce/2015/Aug/msg00001.html
http://packetstormsecurity.com/files/133550/OS-X-Suid-Privilege-Escalation.html
https://support.apple.com/kb/HT205031