Over 4,400 Rockwell PLCs Exposed Online: A Wake-Up Call for Critical Infrastructure Security
In August 2026, Forescout identified 4,407 internet-exposed Rockwell Automation programmable logic controllers (PLCs) worldwide, with 2,844 located in the United States. Notably, 22 of these exposed PLCs were found in cities recently targeted by cyberattacks on U.S. water utilities, with 19 utilizing the same mobile carrier network. Attackers exploited these vulnerabilities by altering IP addresses and setting passwords on accessible controllers, leading to operators losing visibility and control over connected equipment. This incident underscores the critical need for securing industrial control systems against unauthorized internet exposure. The prevalence of internet-exposed PLCs highlights a significant security gap in critical infrastructure, particularly within the water sector. The ease with which attackers can manipulate these systems without exploiting specific vulnerabilities emphasizes the urgency for organizations to implement robust network segmentation, remove unnecessary internet exposure, and enforce strong authentication measures to protect against potential disruptions and threats to public safety.
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