A security accelerator device stores a first credential that is uniquely associated with the individual security accelerator device and represents a root of trust to a trusted entity. The device establishes a cryptographic trust relationship with a client entity that is based on the root of trust, the cryptographic trust relationship being represented by a second credential. The device receives and stores a secret credential of the client entity, which is received via communication secured by the second credential. Further, the device executes a cryptographic computation using the secret client credential on behalf of the client entity to produce a computation result.