A virtual machine or hardware processor for an IC-card portable electronic device includes a non-volatile memory unit, a remote decryption unit, and associated objects for storing an executable program in an encrypted format in the non-volatile memory. The IC-card stores a licence key to encrypt and decrypt the executable program through an IC-card interface. The IC-card interface extracts and encrypts the operands of the plain executable program into encrypted operands so as to not limit performance. The remote decryption unit detects if an instruction contains encrypted operands, and queries a decryption to the IC-card interface. The IC-card interface decrypts the encrypted operands and re-encrypts the just decrypted operands into obscured operands through a dynamic obscuration key.