Cyberattack Disrupts Major U.S. Healthcare Network, Exposing Patient Data A ransomware attack on Change Healthcare, a key subsidiary of UnitedHealth Group, has severely disrupted operations across the U.S. healthcare system, causing widespread delays in prescription processing, insurance claims, and patient care. The incident, first detected on February 21, 2024, forced the company to take critical systems offline, affecting pharmacies, hospitals, and clinics nationwide. The attack has been attributed to the BlackCat (ALPHV) ransomware group, which claimed responsibility and allegedly exfiltrated sensitive data, including patient records and financial information. While UnitedHealth has not confirmed the extent of the breach, reports suggest the hackers may have stolen terabytes of data, raising concerns about potential identity theft and fraud. The fallout has been substantial: pharmacies reported delays in filling prescriptions, healthcare providers struggled with billing disruptions, and some patients faced out-of-pocket costs for medications. The American Hospital Association (AHA) warned of "significant financial strain" on providers, with some smaller clinics at risk of closure due to cash flow interruptions. UnitedHealth has since restored some services, but full recovery remains ongoing. The incident underscores the growing threat of ransomware to critical infrastructure, particularly in healthcare, where delays can directly impact patient safety. Federal agencies, including the HHS and FBI, are investigating the attack, while lawmakers have called for stricter cybersecurity regulations in the sector.