A breach of California Water Service systems in Bakersfield, Visalia and Chico by an Iranian-linked hacking group that surfaced June 11 was limited to a one customer account and an external GPS website, according Cal Water spokeswoman Yvonne Kingman. She wrote in an email that CalWater immediately activated its cybersecurity response plan using Mandiant, a cybersecurity firm that specializes in these types of threats. “Mandiant did not identify evidence of threat actor activity in Cal Water’s internal information technology or operational technology environments,” Kingman wrote in an email. “The investigation determined that the threat actor accessed one active customer’s online Cal Water account using stolen user credentials.”

Related:

• Action News Now (Chico, Calif.): California Water Service provides update on hacking incident involving Iranian hacking group
• KMPH (Bakersfield, Calif.): Iranian-linked hacker group did not breach California water systems, investigation finds