Security News > 2022 > November > Medibank warns customers their data was leaked by ransomware gang
Australian health insurance giant Medibank has warned customers that the ransomware group behind last month's breach has started to leak data stolen from its systems.
The attackers, linked to the REvil cybercrime gang, have leaked a wide range of information so far, including Medibank customers' private and health data and, according to WhatsApp screenshots, negotiation chats with the health insurer's security operations team and CEO David Koczar.
On Monday, before the cybercriminals started leaking data to back their claims and force Medibank into negotiating a deal, the company also disclosed that millions of customers had their information accessed by the hackers.
Passport numbers and visa details for international student customers Health claims data for roughly 480,000 Medibank, ahm, and international customers.
According to Medibank "Given the nature of this crime, unfortunately we now believe that all of the customer data accessed could have been taken by the criminal."
"We will continue to work around the clock to inform customers of what data we believe has been stolen and any of their data included in the files on the dark web and provide advice on what customers should do," the insurer said on Wednesday.