Microsoft has uncovered malicious activity carried out by Volt Typhoon, a state-sponsored actor based in China that typically focuses on espionage and information gathering. Microsoft assesses with moderate confidence that this Volt Typhoon hacking campaign is pursuing development of capabilities that could disrupt critical comms infrastructure between the United States and Asia region during future crises.

https://www.microsoft.com/en-us/security/blog/2023/05/24/volt-typhoon-targets-us-critical-infrastructure-with-living-off-the-land-techniques/