A ‘Colossal’ Ransomware Attack Hits Hundreds Of U.S. Companies, A Security Firm Says

“This is a colossal and devastating supply chain attack.”

A ransomware attack paralyzed the networks of at least 200 U.S. companies on Friday, according to a cybersecurity researcher whose company was responding to the incident.

The REvil gang, a major Russian-speaking ransomware syndicate, appears to be behind the attack, said John Hammond of the security firm Huntress Labs. He said the criminals targeted a software supplier called Kaseya, using its network-management package as a conduit to spread the ransomware through cloud-service providers. Other researchers agreed with Hammond’s assessment.