Keio Railway Confirms Ransomware Attack

Japan’s Keio Corporation confirmed Sunday that ransomware struck its internal network over the weekend. Business systems disrupted. Operational systems: not addressed in initial disclosure.

Keio is one of the Tokyo metropolitan area’s major private railway operators.

The company acknowledged the incident on September 28, 2026. First reported by BleepingComputer. No attacker group has claimed responsibility publicly as of this writing.

Unconfirmed: threat actor identity, ransom demand, data exfiltration scope, whether operational networks were reached.

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