Ransomware Attack on SoftBank’s IDC Frontier Disrupts 495 Japanese Organizations

A ransomware attack on IDC Frontier, a Japanese cloud and data-center provider owned by SoftBank Group, disrupted IDCF Cloud services in East Japan Region 1 and affected 495 companies and local governments. The provider detected unauthorized activity on October 7. Reported downstream impacts included outages of Ibaraki Prefecture’s official and prefectural police websites and a halt to inbound and outbound operations at 17 logistics hubs operated by a Nissui subsidiary.

IDC Frontier isolated and shut down affected systems, engaged external cybersecurity experts, notified law enforcement, and began checking the security of other regions. According to cybersecurity research firm Aviatrix, the attackers claimed they damaged databases, hypervisors, virtual machine disks, and snapshots within seven minutes of breaching the infrastructure; those claims have not been independently verified in the supplied reporting. The attacker’s identity, ransomware family, initial access method, and precise scope remain unconfirmed, while the disruption highlights the operational dependency customers have on shared cloud infrastructure.