On NXP Kinetis KV1x, Kinetis KV3x, and Kinetis K8x devices, Flash Access Controls (FAC) (a software IP protection method for execute-only access) can be defeated by leveraging a load instruction inside the execute-only region to expose the protected code into a CPU register.
kinetis_kv3x_firmware
CVE-2019-14237
On NXP Kinetis KV1x, Kinetis KV3x, and Kinetis K8x devices, Flash Access Controls (FAC) (a software IP protection method for execute-only access) can be defeated by observing CPU registers and the effect of code/instruction execution.