A multimedia device or other type of processing device comprises a memory, a processor coupled to the memory, and playback circuitry coupled to the processor. In one aspect, the processor is operative to control the storage in the memory of at least one multimedia file containing a one-time password or other type of password, where the password is generated externally to the processing device, and to control the playback of the multimedia file via the playback circuitry to make the password apparent to or otherwise accessible to an associated user or other entity. The multimedia file may comprise, for example, an audio file, with the password being presented to the user in an audible form upon playback of the audio file. As another example, the multimedia file may comprise a video file, with the password being presented to the user in a visible form upon playback of the video file.