Dumb question alert: Is it possible that the cosmic background radiation might be the source of dark-matter and/or dark-energy? What is the mass of the background radiation in the known universe?
Neither dark matter nor dark energy can be seen in the electromagnetic spectrum---that's why it's "dark"---whereas the cosmic background radiation is electromagnetic radiation.
We are able to deduce a number of facts about about dark energy and dark matter from their effects on observable stuff (including the CMB in the case of baryon acoustic resonance), but both are strongly excluded from being "stuff as we know it".
I can only elaborate on what's already been said, but no, dark matter and dark energy do not exist as part as the CBR. The CBR we conventionally think of was constructed based on observed EM radiation. Dark matter and energy are only detected currently through their gravitational effects, and won't show up as radiation in the conventional effects, (although I am no expert, I am led to understand that under some models of the theoretical graviton particle, dark matter might radiate gravitons, but don't cite me on that).