A new Princeton University study found that hackers can take control of washing machines, refrigerators, air conditioners, and other connected appliances, to “manipulate the power demand in the grid.” These coordinated attacks can cause local power outages and large-scale blackouts, the study found.

The U.K.-based software company Arm, owned by SoftBank Group, announced on Wednesday a partnership with the Boston-based cybersecurity firm Cybereason to canvass devices connected on a network and offer services to manage their data, the Wall Street Journal reported. Their goal is to scan for vulnerabilities in the IoT network connection to detect malware and other attacks.

“If you look, you will find vulnerability in every device out there,” Lior Div, the CEO of Cybereason told WSJ. “Hackers will use whatever they can.”

A MadIoT attack, or manipulation of demand via IoT, can allow a hacker to take control of 90,000 air conditioners or 18,000 electric water heaters, allowing them to shut down all generators in a specific area, the Financial Times reported based on information from the study.

“It’s the equivalent of a cyber army of controlled devices attacking some of the core services that form the internet,” Justin Lowe, a cyber security expert at PA Consulting told FT. “Anybody producing IoT-type devices needs to think about what they’re doing and understand the wider risk of how their systems could be misused,” said Lowe.

Attacks on internet-connected devices are on the rise, as the technology becomes more available, with a 600% increase in attacks in 2017 from 2016, WSJ reported.