No one. Probably a fine tho and maybe accelerate reguations.

Intent is pretty important here so the user would have to prove that they didn't purposely disguise their prompt as non-nefarious which should be easy and then it stops at #2 and face the litmus test as in did you intentionally make a product for nefarious purposes which from your scenario is unlikely.

agentic loop going haywire and bringing down some government infrastructure then its a different story then everybody is on the hook including the user.

Just wait till one of these agents 'escapes' and is able to persist without human help by hacking and stealing resources.