Ransomware attack occurred on August 31, 2025 at University of Hawaii Cancer Center. Attack affected a single research project without impacting clinical operations. Systems were encrypted causing extensive damage and delaying restoration efforts. Research files were stolen including historical documents from the 1990s containing Social Security numbers. University paid ransom to obtain decryption tool and secure destruction of stolen data. Most affected files contained research data without personal identifiers, but some older files from 1990s contained SSNs used before different identification methods were adopted.