Self-adapting and mutating LLM based viruses/worms

I am thinking about a future of malware and cyber worms. I bet it's gonna be self-mutating and adapting to local environment using local models (once they are built-in to all devices and performant enough in future years). Basically almost a real organism resembling real biological viruses. In this case the non-determinism of LLMs is a feature. Every infection could take its own development path - and half might die, half might survive. Think genetic programming but autonomous and on steroids. For some non tech (even tech?) people this reminds Skynet and it's fascinating that we are in a trajectory that this suddenly imaginable and theoretically soon possible.

Why is not happening now? Inference is still expensive and local models are not there yet, so there's no ROI in making this at scale. But once inference is local and cheap as electricity or running water, this is the natural development. How do we stop the spreading then?

Are there already some documented experiments?