What appears to be the decryption key for Apple’s Secure Enclave Processor (SEP) firmware was posted online by a hacker going by the name of xerub.
A coprocessor fabricated in the Apple S2, Apple A7, and later A-series CPUs, SEP uses encrypted memory, has a hardware random number generator and “provides all cryptographic operations for Data Protection key management and maintains the integrity of Data Protection even if the kernel has been compromised,” Apple explains in the iOS Security Guide.
At startup, the device creates an ephemeral key entangled with the UID (Unique ID), and uses it to encrypt the Secure Enclave’s portion of memory space. The key is also used to authenticate the Secure Enclave (except on Apple A7).
