Keio Corporation Hit by Ransomware Attack Disrupting Business Systems

• •Keio Corporation confirmed a ransomware attack on September 26, 2026.
• •The attack disrupted business systems, particularly affecting the hospitality division.
• •No confirmed information leakage has been reported, but investigations are ongoing.

Keio Corporation, a major private railway operator in Japan, confirmed a ransomware attack on September 26, 2026, which disrupted its business systems, particularly affecting its hospitality division. The company has shut down its network to prevent further damage and is investigating the extent of the impact, including potential customer information leakage. While the attack has caused difficulties in some systems, Keio has not confirmed any information leakage as of now. The incident also coincided with a cyber incident at Tokyo Metro, which reported unauthorized access to 59,000 member email addresses. Keio has reported the incident to the police and is working with external experts to assess the damage. The attack appears to have only impacted the hospitality side of Keio's business, with no disruption to train operations reported. Local media indicated that the cyberattack affected payment systems, causing delays in customer-facing services.