Poking physics with network packets¶

Operational technology security is where a misconfigured register ceases to be a finding and becomes a bang, a spill, or a process that drifts quietly out of spec for six weeks before anyone notices. The protocols are decades old and were designed for reliability, not security: they trust commands that look normal, they do not authenticate the engineer behind them, and they assume that anyone who can send a valid Modbus frame belongs there.

The attack pattern that actually works here is not Stuxnet’s bespoke precision engineering. It is a corporate laptop with VPN access and a route to the historian server. Air gaps are mostly mythology; the real topology is a flat network with a firewall that nobody has reviewed since the last integrator visit. From there, the engineering workstation holds the logic definitions, the credentials, and the deployment tools that make “authorised maintenance” look exactly like an attack when the wrong person does it.