Patent ID: 8166561

Claim:
A security device, comprising: a first external interface; a second external interface; and a security controller connected to said first external interface and said second external interface, said security controller being adapted to: validate an access right based on a codeword received via said first interface to perform an encrypted memory access via said second external interface to an external memory coupleable to said second external interface, and prevent said encrypted memory access via said first external interface or prevent any output of data via said first external interface with the data output depending on encrypted data received via said second external interface, in case of a negative validation, wherein the first external interface is a male USB connector and the second external interface is a female USB connector with the external memory being a USB stick, or the first external connector is a male USB connector and the second external connector is a memory card slot connector with the external memory being a memory card, and wherein said security controller is adapted to: in case of the negative validation, prevent said encrypted memory access via said first external interface from causing any changes of a memory content of the memory card via said second external interface and any leaking of the memory content to outside via the via said first external interface, and, in case of a positive validation, completely execute said encrypted memory access; perform said encrypted memory access in case of a positive validation: by encrypting data received via said first external interface or data derived there from using an encryption algorithm and outputting the encrypted data received via said first external interface to said external memory via said second external interface; and/or by decrypting the encrypted data received from said external memory via said second external interface using a decryption algorithm and outputting said decrypted data or data derived there from via said first external interface; and use said codeword at least as part of an encryption key for said encryption algorithm or at least as part of a decryption key for said decryption algorithm.