Keio Corporation confirms ransomware attack disrupts business systems

Keio Corporation, a major Japanese railway and hospitality operator, confirmed that its group servers were targeted by a ransomware attack in the early hours of September 26, 2026. The company took immediate action to shut down its network to prevent further damage.

The attack has caused disruptions to certain business systems, specifically affecting the hospitality side of the business, including the Keio Plaza Hotel. Local reports indicate that payment systems have been impacted, leading to potential delays in customer-facing services. However, the company stated that train operations remain unaffected.

Keio is currently investigating the scope of the incident, including whether any customer or business partner information was accessed. As of the latest updates, no data leaks have been confirmed. The company is working with the police and external experts to determine the attack route and extent of the damage.