Japanese cloud provider IDC Frontier hit by ransomware attack

What happened

Japanese cloud and digital infrastructure company IDC Frontier disclosed that its IDCF Cloud service was subjected to a ransomware (software that locks up files and demands payment) attack. Cloud Security , Ransomware Japanese cloud provider IDC Frontier hit by ransomware attack October 11, 2026 Share By SC Staff Following insights from Bleeping Computer, Japanese cloud and digital infrastructure company IDC Frontier disclosed that its IDCF Cloud service was subjected to a ransomware attack.

local time, forced IDC Frontier to shut down its network and systems. The company confirmed that a third party's ransomware attack caused the disruption in East Japan Region 1, impacting approximately 495 companies and local governments.

IDC Frontier, a subsidiary of SoftBank Group, isolated and shut down affected systems to prevent further spread. This incident led to an outage affecting a data center (a building full of computers that runs online services) cluster that serves the eastern region of Japan. The threat actor (the person or group behind an attack) claims to have encrypted 225 databases, totaling 3.6 petabytes of data, and compromised numerous virtual machines and snapshots.