Extrapolating this, we should expect this kind of breach to occur more often. Humans are simply not capable of contemplating every fail scenario for swarms of thousands of intelligent autonomous agents which can seamlessly and instantly share knowledge. We need independent audit and monitoring systems to assess the intent of each task and align it - in real time. This is far harder than it may first appear.
There is also a broader discussion about social utility. Cars are fantastic, but 37,000 people die every year from car accidents. We accept that there is no way to make cars perfectly safe, so we accept the cost relative to the benefits. I think we might have to make a similar bargain with AI. The problem is that the potential costs are far higher with AI, and they're not easy to predict.