Hundreds of American businesses have been hit by a ransomware attack after an incident at the Miami-based IT firm Kaseya, potentially marking the latest in a line of hacks destabilizing US companies.

This is a colossal and devastating supply chain attack. Kaseya is plugged in to everything from large enterprises to small companies “it has the potential to spread to any size or scale business.”

Kaseya, in a statement posted on its own website, said it was investigating a “potential attack” on VSA, a widely used tool to reach into corporate networks across the USA. Kaseya tool offers to monitor and manage servers, desktops, network devices and printers and that it may have been attacked. Urging customers to switch of the servers immediately.

It’s believed the Russia-linked REvil ransomware gang – the same group of actors blamed by the FBI for paralyzing meat packer JBS last month – was behind the latest ransomware outbreak.

Supply chain attacks have crept to the top of the cybersecurity agenda after hackers alleged to be operating at the Russian government’s direction tampered with a network monitoring tool built by Texas software firm SolarWinds.

Kaseya has 40,000 customers for its products, though not all use the affected tool.