Steel Mills
Nucor reports IT systems breach
Written by Stephanie Ritenbaugh
May 14, 2025
Nucor Corp. reported a cybersecurity breach of its IT systems.
In a filing with the US Securities and Exchange Commission, Nucor said it identified an incident “involving unauthorized third-party access to certain information technology systems used by the company.”
The Charlotte, N.C.-based steelmaker said it took the affected systems offline and implemented other containment, remediation, or recovery measures.
“The company is actively investigating the incident with the assistance of leading external cybersecurity experts and has notified federal law enforcement authorities,” Nucor said in the May 13 filing.
The steelmaker said it temporarily and proactively halted some production operations at various locations.
A spokeswoman declined to specify which locations were affected.
“Despite this interruption, we are taking care of our customers and are in the process of restarting the affected operations,” the spokeswoman said.
Nucor is the largest steelmaker in North America with 26 US-based mills and more capacity coming online.
Stephanie Ritenbaugh
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