The U.S government warned industrial firms this week about a hacking campaign targeting the nuclear and energy sectors, the latest event to highlight the power industry's vulnerability to cyber attacks.
Since at least May, hackers used tainted "phishing" emails to "harvest credentials" so they could gain access to networks of their targets, according to a joint report from the U.S. Department of Homeland Security and Federal Bureau of Investigation.
The report provided to the industrial firms was reviewed by Reuters on Friday. While disclosing attacks, and warning that in some cases hackers succeeded in compromising the networks of their targets, it did not identify any specific victims.
"Historically, cyber actors have strategically targeted the energy sector with various goals ranging from cyber espionage to the ability to disrupt energy systems in the event of a hostile conflict," the report said.
Homeland Security and FBI officials could not be reached for comment on the report, which was dated June 28.
The report was released during a week of heavy hacking activity.
A virus dubbed "NotPetya" attacked on Tuesday, spreading from initial infections in Ukraine to businesses around the globe. It encrypted data on infected machines, rendering them inoperable and disrupting activity at ports, law firms and factories.
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