Every American's social security number may have been compromised in a massive cyber security breach that can threaten the identity of all citizens.

USDoD hacking group the claims that they leaked 2.7 billion records of personal information, including social security numbers, full names and home addresses from a data broker called National Public Data (NPD).

Related: Hack exposes 10 billion passwords, largest leak in history

NPD is a background check agency that provides sensitive personal information to potential employers and staffing agencies during screening processes, as well as to private investigators.

According to one collective actionThe NDP obtained the data without consent and the breach occurred sometime in April 2024.

The lawsuit alleges that “upon information and belief” the USDoD was “able to exfiltrate the unencrypted PII of billions of individuals” and that personal information was “published, offered for sale and sold on the Dark Web by cybercriminals.”

According to Computer Bleepingthe records were leaked for $3.5 million.

How do I know if I've been hacked?

There are several ways to check if your personal information has been leaked.

First, monitor your credit reports and look for unauthorized or fraudulent activity, including opening new bank accounts, credit cards or large withdrawals.

Related: Mark Cuban warns after his Google account was hacked

If you receive notice from a debt collector or notice fraudulent activity, contact your financial institutions and law enforcement.

Also, be the first to initiate calls (meaning if you get a call, tell them you'll call back) and don't give out your social security number.