Keio and Tokyo Metro disclose breaches: ransomware attack and 59,000 emails

Japanese railway operator Keio Corporation confirmed a ransomware attack on September 26, 2026, and shut down part of its network; trains are running normally and no data leak has been found so far. Tokyo Metro said an unauthorized third party accessed the email addresses of about 59,000 Metpo loyalty program members.

• Keio confirmed a ransomware attack on September 26, 2026
• The company shut down part of its network; trains run normally
• Tokyo Metro: emails of about 59,000 Metpo members exposed
• Keio Plaza Hotel also reported disruptions to its systems