UnitedHealth Group CEO Andrew Witty revealed new details about the cyberattack on its Change Healthcare unit earlier this year, and said the company has been working around the clock to fully restore its systems following the widespread outages from the attack. In prepared remarks before the Senate Finance Committee on Monday, Witty said the perpetrator of the Feb. 21 hack was a cybercriminal known as Blackcat or ALPHV, confirming earlier reports that the ransomware group had taken credit for the attack. Th ...