Cybercriminals have breached insurance giant Aflac, potentially stealing Social Security numbers, insurance claims and health information, the company said Friday, the latest in a spree of hacks against the insurance industry.

It's possible that Social Security numbers may have been compromised. It's unclear how many people may have been affected.

It’s the largest insurance company yet to fall victim to a major hacking, with tens of millions of customers and a $55 billion market cap.