Patent attributes
There is described a challenge-response method for a computing device. The method comprises steps of: (a) receiving challenge data at a secured module of the computing device, the challenge data comprising image content encrypted using an encryption key, and the image content including a nonce; (b) the secured module recovering the image content through decryption using one or more keys associated with the encryption key; (c) the secured module of the computing device outputting the recovered image content; (d) capturing the image content as output by the secured module; (e) processing the captured image content so as to obtain the nonce; and (f) providing the nonce as a response. There is also described a computing device arranged to carry out the challenge-response method, a computer program for causing a processor to carry out the challenge-response method, and a computer readable medium storing such a computer program.