The New York Times reports:

The scope of cyberattacks on U.S. water systems has grown to include at least seven states and may be far wider, officials and experts warned, as the authorities raced to safeguard the nation’s water supply against an assault that increasingly appeared to be the work of Iran.

While there were no indications that any water supply had been altered or made unsafe to drink, state and local officials throughout the country were on high alert for potential problems in vulnerable computers that are commonly used to monitor and adjust water quality, including chemical-treatment levels and water pressure. Minnesota first publicly reported the attacks, and now Michigan says its systems have also been targeted.

The attack has little precedent, experts said, but has long been the stuff of nightmares and sensationalized Hollywood thrillers: an apparent cyberattack by a foreign power during a time of war that could, at least in theory, jeopardize the health and safety of Americans.

Officials cautioned that they had not definitively determined that Iran was responsible for the attack and that the investigation was still preliminary. But they said Iran had stepped up cyberattacks since the U.S. and Israel launched a war against the country five months ago, and had previously targeted similar water systems and other critical infrastructure in the U.S. There seemed no financial motive, making a criminal attack less likely.

Despite growing concerns, President Trump sought to downplay the matter on Friday by blaming Minnesota — which was early to spot and report the recent surge in malicious hacking activity, helping to prompt other states to probe their own water systems — for suffering intrusions his own intelligence agencies believe were highly likely carried out by Iran, officials familiar with the assessment said.

“I think Minnesota is behind it,” Mr. Trump said on Friday in response to a reporter’s question about Iran’s possible involvement, which The New York Times earlier reported. “I don’t think there was an Iranian cyberattack.”

The state’s Democratic governor, Tim Walz, dismissed the accusation, warning in a social media post that this “is what modern warfare looks like.”

After Mr. Trump’s remarks, federal officials privately said Iran remains the top suspect but that the assessment remained preliminary and had not yet established definitive forensic proof. That is not unusual in complex cyber-investigations, which can often take months to reach authoritative conclusions, if at all.

Nate George, the mayor of Braham, a small city north of Minneapolis that was among those affected by the cyberattack, said federal and local officials had little doubt about the likely culprit.

“We’re getting bits and pieces of information from the state of Minnesota and the F.B.I.,” he said in an interview on Friday afternoon. “They are pretty sure it’s Iranian actors” but are reluctant to say so publicly, he added. A memo sent by an industry group that shares cyberthreat information among water utilities that was obtained by Wired magazine said the attacks aligned with hacking activity being conducted by Iran-affiliated actors. [Continue reading…]