All Breaches
Keio Corporation Data Breach
In September 2026, Keio Corporation, a major Japanese railway, transit, and retail conglomerate operating across the Greater Tokyo Area, disclosed a ransomware intrusion affecting its central server network and subsidiary systems.
Not disclosed
Affected People
5
Data Types
Not rated
Severity
Oct 27, 2026
Last updated
The organization has not published how many were affected, so the incident cannot be placed on this scale.
Exposed Data Types
5- Names
- Email addresses
- Phone numbers
- Physical addresses
- Reservation and travel information
About This Breach
Claimed by the Qilin ransomware syndicate in October 2026, the breach disrupted internal email and reservation platforms and exposed corporate, employee, and customer records.
Verification and editorial method
LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.
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