YOKOSUKA GAKUIN — Ransomware Incident Claimed by Rhysida
- Victim: YOKOSUKA GAKUIN
- Claimed by Rhysida
- Date claimed: 2025-12-15
- Country: JP
- Sector: Education
- Severity: Critical
Rhysida listed YOKOSUKA GAKUIN, an Education organization, as a victim on its data-leak site (2025-12-15).