UnitedHealth Data Breach Hits 190 Million Americans in Worst Healthcare Hack

Nearly 190 million Americans were affected by February’s cyberattack on UnitedHealth’s Change Healthcare unit, almost double initial estimates, the company disclosed Friday. The breach, the largest in U.S. medical history, exposed sensitive data including Social Security numbers, medical records, and financial information.

UnitedHealth said it has not detected misuse of the stolen data or found medical databases among compromised files. Change Healthcare, a major U.S. healthcare claims processor, paid multiple ransoms after Russian-speaking hackers known as ALPHV breached its systems using stolen credentials lacking multi-factor authentication, according to CEO Andrew Witty’s testimony to Congress.