The companies that run such equipment, particularly the electric utilities that serve as the most fundamental layer on which the rest of the industrialized world is built, constantly offer the public assurances that they have a strict “air gap” between their normal IT network and their industrial control network. But in a disturbing fraction of cases, those industrial control systems still maintain thin connections to the rest of their systems—or even the public internet—allowing engineers to access them remotely, for instance, or update their software.
