Nucor Corporation, a leading U.S. steelmaker, suffered a cyberattack on May 13, 2025, which led to unauthorized access to their computer systems. The company proactively shut down production operations at multiple steel manufacturing facilities as a safety measure. The volume of compromised data was described as 'limited,' and the company is still reviewing what information was stolen. All production facilities have resumed normal operations, and the hackers no longer have access to company systems.
Source: https://cybersecuritynews.com/steelmaker-nucor-hacked/
TPRM report: https://scoringcyber.rankiteo.com/company/nucor-corporation
"id": "nuc603062325",
"linkid": "nucor-corporation",
"type": "Breach",
"date": "6/2025",
"severity": "100",
"impact": "5",
"explanation": "Attack threatening the organization's existence"{'affected_entities': [{'industry': 'Steel Manufacturing',
'location': 'Charlotte, U.S.',
'name': 'Nucor Corporation',
'type': 'Steelmaker'}],
'data_breach': {'data_exfiltration': 'yes',
'type_of_data_compromised': 'limited datasets'},
'date_detected': '2025-05-13',
'description': 'A leading U.S. steelmaker, Nucor Corporation, suffered a '
'cyberattack where hackers gained unauthorized access to their '
'computer systems on May 13, 2025. The company proactively '
'shut down production operations at multiple steel '
'manufacturing facilities as a safety measure. The company '
"describes the volume of compromised data as 'limited' and is "
'still reviewing what information was stolen. All production '
'facilities have resumed normal operations, and the hackers no '
'longer have access to company systems.',
'impact': {'data_compromised': 'limited',
'downtime': ['temporary production shutdowns',
'temporary limitations to IT applications'],
'operational_impact': 'multiple facilities within Nucor’s '
'nationwide network of steel production '
'plants',
'systems_affected': ['production operations',
'information technology applications']},
'investigation_status': 'ongoing',
'references': [{'source': 'SEC filing report'}],
'regulatory_compliance': {'regulatory_notifications': 'yes'},
'response': {'communication_strategy': 'appropriate notifications to affected '
'parties and regulatory agencies',
'containment_measures': ['network segmentation',
'taking affected systems offline'],
'incident_response_plan_activated': 'yes',
'law_enforcement_notified': 'yes',
'network_segmentation': 'yes',
'recovery_measures': 'restored all affected production '
'operations',
'remediation_measures': ['additional security controls',
'network hardening measures'],
'third_party_assistance': 'external cybersecurity specialists'},
'title': 'Cyberattack on Nucor Corporation',
'type': 'Cyberattack'}