A security module includes a signal interface for receiving an encrypted signal and a host interface that is coupleable to a host. A processing module is operable to receive encrypted decryption code from the host via the host interface, decrypt the encrypted decryption code to form decrypted decryption code that is operable to decrypt the encrypted signal, send the decrypted decryption code to the host via the host interface, monitor the security of the decrypted decryption code via security signaling sent between the host and the security module via the host interface to detect potential tampering with the decrypted decryption code, transfer the encrypted signal to the host via the host interface, and discontinue transfer of the encrypted signal when the security signaling indicates the potential tampering with the decrypted decryption code.