A cybersecurity incident on Nucor Corporation’s systems, the largest steel producer in the U.S., forced the company to take offline parts of its networks and implement containment measures.
The incident caused the company to temporarily suspend production at multiple locations, although the full impact on Nucor’s business remains unclear.
Nucor is a major steel producer in the U.S. and scrap recycler in the North America. It is a primary supplier of reinforcing bar that is used extensively in the country’s buildings, bridges, roads, and infrastructure.
The company employs more than 32,000 people across numerous mills across the U.S., Mexico, and Canada, and reported a $7.83 billion revenue in the first quarter of the year.
The cybersecurity incident was disclosed via an 8-K filing the firm submitted earlier today to the U.S. Securities and Exchange Commission (SEC).
“Nucor Corporation recently identified a cybersecurity incident involving unauthorized third party access to certain information technology systems used by the Company,” reads the SEC filing.
“Upon detecting the incident, the Company began promptly taking steps to contain and respond to the incident, including activating its incident response plan, proactively taking potentially affected systems offline and implementing other containment, remediation, or recovery measures.”
Nucor also stated that it has notified law enforcement authorities and engaged with external cybersecurity experts to assist with the investigation.
Meanwhile, certain production operations at various locations were halted, though Nucor notes it is in the process of gradually restarting them.
No details about the date or type of the attack were provided, so it’s unknown if the incident involved data theft or encryption.
At the time of writing, no ransomware groups have assumed responsibility for the attack at Nucor, so the perpetrators are unknown.
BleepingComputer has contacted the company to ask more information about the incident, but we are still waiting for a response.
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