UnitedHealth says Change Healthcare hack affects over 100 million, the largest-ever US healthcare data breach

A February ransomware attack on Change Healthcare—attributed to the ALPHV/BlackCat ransomware group and associated contractors—led to widespread outages across the U.S. healthcare sector and the theft of data for over 100 million individuals, including personal identifiers (SSNs, driver’s licenses, passports), health records, and financial/claims data. UnitedHealth Group paid ransom(s) to recover a copy of the stolen dataset, enabling notifications, while investigations focus on missing multi-factor authentication, the scale of centralized health-data aggregation following corporate mergers, and ongoing extortion and leak activity.