UnitedHealth Group has been hit by a cyberattack, attributed to Russian ransomware group Blackcat, affecting its subsidiary Change Healthcare. The attack, which has led to an eight-day outage, is impacting pharmacies, hospitals, and startups, with executives warning it could soon escalate into a crisis. The hackers claimed responsibility, stating they stole 'millions' of records and allegedly obtained 6TB of data. UnitedHealth now believes cybercriminals were behind the disruptive attack. Shares of UnitedHealth ($UNH) are on pace for a third straight monthly decline following the incident. An executive from UnitedHealth Group suggested that the outage could persist for weeks.