University of Hawaii Cancer Center Breach Exposes SSNs of 87,000+ Participants

The University of Hawaiʻi Cancer Center experienced a ransomware attack discovered in August 2025 that encrypted research servers and potentially exposed historical research files containing names paired with Social Security numbers and driver’s license numbers. Approximately 87,493 Multiethnic Cohort participants and up to 1.15 million additional individuals may have been impacted; the university engaged third-party investigators, obtained a decryption tool from the threat actors, is notifying affected individuals, and has implemented systemwide security improvements.