A massive data breach at a Florida background-check company has exposed the private information — including Social Security numbers — of some 2.9 billion people to the dark web.

Coral Springs-based National Public Data, operated by Jericho Pictures Inc., specializes in criminal records and background checks. A hacker known as "Fenice" reportedly raided NPD's database and leaked records that included personal data such as full names, addresses, and Social Security numbers.

National Public Data hasn't yet disclosed how or when the breach occurred.

If confirmed, the breach would rival the scope of the 2013 hack of Yahoo, which leaked private info of some 3 billion people worldwide.

Jericho Pictures is already facing a class-action lawsuit, filed Thursday, over an April incident in which a hacker known as "sxul" claimed to have breached NPD's database and accessed information.

Days later, another hacker group known as USDoD got involved and posted the stolen data on sale for $3.5 million. It's unclear if the data was actually sold.

Authorities believe USDoD is based in Latin America.

Cybersecurity experts say the breach is likely to affect most Americans — and even relatives who've been dead for decades — unless they've paid for "opt-out" services. The company has not yet alerted anyone inside or outside the U.S. about the potential breach, the Daily Mail reported.

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