Local verification of code authentication

Embodiments are directed to a computing device having execution hardware including at least one processor core, and non-volatile memory that stores verification module and a private symmetric key unique to the computing device. The verification module, when executed on the execution hardware, causes the execution hardware to perform pre-execution local authenticity verification of externally-supplied code in response to a command to launch that code. The local authenticity verification includes computation of a cryptographic message authentication code (MAC) of the externally-supplied code based on the private symmetric key, and verification of the MAC against a stored local authenticity verification value previously written to the non-volatile memory. In response to a positive verification of the of the MAC, execution of the externally-supplied code is permitted.