Over 530K impacted by Wisconsin healthcare non-profit ransomware attack

Group Health Cooperative of South Central Wisconsin had data from 533,809 individuals compromised following a ransomware attack in late January, which the BlackSuit ransomware operation had claimed, BleepingComputer reports.

After infiltrating GHC-SCW's network on Jan. 25, attackers were able to exfiltrate individuals' names, birthdates and/or death dates, telephone numbers, home and email addresses, Social Security numbers, and Medicare and/or Medicaid numbers, said the non-profit managed healthcare provider in a press release.

Despite the intrusion, impacted systems were immediately restored following threat actors' failure to conduct device encryption, noted GHC-SCW, which also noted bolstering its security controls and user training to curb future breaches.

Such a development comes weeks after BlackSuit, which is a rebrand of the Royal ransomware group, took responsibility for the intrusion, with the ransomware gang also claiming the theft of the non-profit's business contracts and email messages, as well as its employees' data and patient financial details.