Capita PLC (LSE:CPI)'s pension fund members have been notified that their data was compromised in a cyber attack in March, which also affected private-sector retirement schemes using the firm's administrative services, according to the Times.
The paper estimates that details of over half a million UK private sector pension scheme members could have been stolen as part of the Russian hack.
Several pension scheme members are considering legal action, with law firm Barings Law having initiated proceedings. The attack also impacted NHS England, revealing the names and NHS numbers of deceased and deregistered patients.
The latest details on the cyber attack were contained in a letter seen by the Times.
Despite criticism for its data handling, Capita has continued to secure contracts, most recently from the City of London Police for operating a contact centre for reporting fraud and cybercrime.
This disclosure follows a warning by PwC pension fund trustees about compromised member information, including birth dates and retirement details.