One approach for authenticating data includes storing a plurality of combinations of representations of public keys and session key IDs in a non-volatile memory. A payload and accompanying public key, session key ID, and signature of the payload are input. The signature is a function of the payload and a private key of a key pair that includes the accompanying public key and the private key. Authenticity of the payload is determined based on the accompanying public key and session key ID and the combinations stored in the non-volatile memory, and from the signature and the payload. In response to determining that the payload is authentic, the payload is processed, and in response to determining that the payload is not authentic, processing of the payload is disabled.