Customers who have insurance through Aflac may have had their data stolen: earlier this month, the company experienced a cyber attack that compromised personal information belonging to an unknown number of its approximately 50 million policyholders.

A group of cybercriminals hacked into data systems at insurance company Aflac, possibly gaining access to sensitive information such as Social Security numbers and health reports, the company said on Friday.

Aflac recently revealed that hackers stole its customers' data in a cyberattack. Details remain scarce, but the company says it "was caused by a sophisticated cybercrime group" that's targeting the insurance industry.