libxpc in Apple iOS before 8.4.1 and OS X before 10.10.5 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app that sends a malformed XPC message.
Improper Restriction of Operations within the Bounds of a Memory Buffer The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.