Smart Sprinklers Are Also Part of the IoT: And They’re Vulnerable

Modern homes have adopted a wide variety of Internet-of-Things products to regulate various resources, such as water or electricity. Vulnerabilities in these devices could spell disaster for the regular user, who can incur increased costs and potentially contribute to wasting the city’s supplies.

But consumer IoT devices are not confined to the home.

A research paper published this month presents a distributed attack model aimed at smart irrigation systems that automate watering of gardens or lawns. Researchers at Ben Gurion University analyzed three smart sprinklers and found vulnerabilities that let an attacker control the water flow.

After studying how GreenIQ and BlueSpray smart sprinklers work, the researchers observed that their connection to the cloud server was not encrypted. This allows an attacker on the same network to intercept the traffic and alter commands to the irrigation system, in what is called a man-in-the-middle attack.

Getting on the local network is far from difficult; the researchers posit that an attacker could rent botnet services to create a network of infected devices that search for smart sprinklers on their network. “If no connected smart irrigation systems are found, the bot destroys itself in order to cover its tracks,” adds the research paper.

The Rainmachine smart sprinkler can adjust its watering operations automatically according to data received from the Norwegian Meteorological Institute weather forecast services. After looking into its firmware, the researchers were able to spoof the forecast information because the service delivered the information via an unencrypted connection.

Targets were detected on the local network by analyzing traffic information for connections to the cloud service of any of the three irrigation systems. This was possible because the sprinkler manufacturers don’t make other IoT products. The entire process took 15 minutes from the moment the compromised devices initiated the search.

The researchers say that attacking automated consumer watering systems could impact a city’s water supply. According to their calculations, a botnet of 1,355 sprinklers could empty a standard water tower in less than an hour; 23,866 working for six hours would empty a small flood water reservoir.

However, the impact is on the consumer rather than a water company, which uses control mechanisms to measure and control the flow specifically to make sure they don’t dry up.

GreenIQ sprinklers currently encrypt communication with the cloud server and closed the SSH port that could be used by an attacker to run malicious code. Norwegian Meteorological Institute also ran an upgrade that encrypts the traffic with the clients.

Image credit: Ben Gurion University