A method and system for hiding authentication data within a multimedia data stream provides for cross-authentication. The method includes the step of obtaining a first set of authentication data, where the first set of authentication data is based on data contained in a first media channel of the multimedia data stream. The method further includes the step of hiding the first set of authentication data in a second media channel of a multimedia data stream. When dealing with active data streams, the present invention provides for hiding a first subset of the active data stream in a visual channel of the multimedia data stream. A second subset of the active data stream is then hidden in the audio channel of the multimedia data stream. In one embodiment, the first subset includes executable content, where the second subset includes a controlled data stream.