runner in Install.framework in the Install Framework Legacy component in Apple OS X before 10.10.5 does not properly drop privileges, which allows attackers to execute arbitrary code in a privileged context via a crafted app.
https://www.exploit-db.com/exploits/38137/
https://support.apple.com/kb/HT205031
http://www.securitytracker.com/id/1033276
http://www.securityfocus.com/bid/76340
http://lists.apple.com/archives/security-announce/2015/Aug/msg00001.html