If your network isn't air gapped, then it's vulnerable, and attackers will side step the "read only" path to affect control system changes.
It can be implemented with a fiber optics cable with only the transmitter on the secure side, a laser+photo cell for real air gap, cutting the rx cable in a rs232 or having a microcontroller with an output pin connected to another controllers input pin. By handling it with hardware instead of software you get a very secure partition between the trusted and untrusted side.
It's used to monitor for example industrial systems and power plants.
Wikipedia calls it unidirectional network: https://en.wikipedia.org/wiki/Unidirectional_network
You can't drive my car simply by pointing a webcam on the steering wheel.
My position is that if there's any connection, of any practical type, between the control system and the outside world, an attacker will be able to find ways to break things.
Even if it just boils down to "an attacker made our dashboards report numbers wrong and so we closed a valve to prevent an issue that didn't exist, and inadvertently destroyed our own product", the outcome is the same.
Temperature sensor is a sensor. Refrigeration compressor motor is an actuator.
GPS positioning of a car is a sensor. Motor to turn the wheel is an actuator.
Aircraft altimeter is a sensor. Motors to control control surfaces are actuators.
And so on.
Some devices are sensors, like temperature sensors. It's not that they're "read only", it's that... You can't override temperature. For that, you need other devices. Like a switch to a motor that operates refrigeration compressor. That would be an actuator. If you put the data from the sensor online, the worst case scenario is someone unauthorized gets your data. If you build interface to control an actuator online... You can read the article up top.
The problem is that all major cloud providers (AWS and Azure for sure, and I'm sure Google as well) have a large number of services targeting IoT devices, both to read and control. So default architectural decision is "We'll just plug these into AWS IoT, it's secure, reliable, highly available, and has all the features we need, all we have to do is to configure what we want and we're all set". Which in reality is not that secure just because of how IoT is designed. But AWS/Azure obviously push for these solutions because it gives them more revenue.
It’s a very low margin business if you don’t work efficiently you’ll get outcompeted by people who do like Aldi/ Trader Joe’s etc
Most of the HVAC based control system changes are about saving energy, not labor.
or find any exposed Ethernet slot and slide your device in it.
most of the time it will work and you will get an inside access.
publicly available retail stores require multiple layers of defense across the L7 stack
Dear god I hope the moron manager responsible for that got their bonus revoked
I understand why it's beneficial to have these systems connected to a network. You have not explained why that network has to be the Internet, and TFA is one reason why it shouldn't be.
That doesn't really make a ton of sense. Stores have personnel in them pretty much all the time, who can take action when necessary. Data collection for monitoring, forecasting, etc. is a reasonable thing to do obviously, and centralized aggregation clearly makes sense. But remote control smells more like a fanciful shiny tech bauble than an actually useful, let alone necessary, feature. It's easy to imagine how that feature got sold internally within an engineering organization, but it's very hard to imagine customers clamoring for it.