Various infostealers are most likely the culprit.
Jefferson County Clerk Bobbie Holsclaw has said no personal information was compromised in the attack.
The suit was filed Dec. 14 on behalf of those who are or were patients or were affiliated with Norton.
The money will be invested over the next several years in an effort to advance the university's "national leadership in microelectronics and nanotechnology."
The exercises were meant to mimic emergency situations that the city could face to enhance preparedness for coordinated attacks.
Norton said it received a "suspicious message" on May 9 and took several systems offline as a precaution.
Unemployment officials are working with the Kentucky Office of Homeland Security, the state's Labor Cabinet and the Commonwealth Office of Technology to address the attack.
Already this year, e-skimmer criminals are active, according to research from RiskIQ.
A top banking regulator has fined Capital One $80 million over a data breach last year that exposed the personal information of more than 100 million people.
The FBI’s Protected Voices initiative aims to educate the public about foreign influence.