sys/openbsd/stack_protector.c in libc in Apple iOS 6.1.3 and Mac OS X 10.8.x does not properly parse the Apple strings employed in the user-space stack-cookie implementation, which allows local users to bypass cookie randomization by executing a program with a call-path beginning with the stack-guard= substring, as demonstrated by an iOS untethering attack or an attack against a setuid Mac OS X program.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.