An issue was discovered in certain Apple products. macOS before 10.12.3 is affected. The issue involves the "Graphics Drivers" component. It allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app.
Apple Security Advisory 2017-01-23-2 - macOS 10.12.3 is now available and addresses suffers from code execution and various other security vulnerabilities.