Beginning around 2012, Russian hackers started probing American energy companies and electrical utilities. Three years later, in 2015, they used similar access to Ukraine’s utility companies to shut off the power for several hours to Western Ukraine, and again one year later to Ukraine’s capital, Kyiv.
In 2017, Russian hackers reached far enough into an American power plant to manipulate its controls, stopping just short of sabotage. That same year, hackers in Russia were caught dismantling the safety locks at a Saudi petrochemical facility that prevent catastrophic explosions.
In recent years, the United States has escalated its own cyberattacks against Russia, with a series of strikes on Russia’s power grid, in what cybersecurity experts have likened to the digital equivalent of mutually assured destruction.
Other nations have probed American systems, too. In 2013, Iranian hackers were caught manipulating a small dam in New York. Officials initially feared Iran’s hackers were inside the much larger Arthur R. Bowman dam in Oregon, where a cyberattack that dismantled the locks on the dam could have resulted in calamity. But investigators determined the hackers were instead inside the much smaller Bowman Avenue dam that holds back a babbling brook in New York, 30 miles north of Manhattan.
It is attacks on these smaller municipal systems, like the Bowman Avenue dam and the water treatment facility in Oldsmar, that cybersecurity experts say they most fear. While large utility companies usually have complex protections in place, smaller water supply companies, electric power suppliers and manufacturers often do not.
“These are the targets we worry about,” said Eric Chien, a security researcher at Symantec. “This is a small municipality that is likely small-budgeted and under-resourced, which purposely set up remote access so employees and outside contractors can remote in.”
That, Mr. Chien said, makes them a ripe target.
Oldsmar has disabled remote access, said Al Braithwaite, the city manager. “We anticipated that this day was coming,” he said. “We talk about it, we think about it, we study it.”