OKLAHOMA CITY - Their job was to protect your personal information but a security breach exposed 143 million peoples' most private details, including birth dates, social security numbers and driver's license numbers.
News 4 spoke with the Better Business Bureau of Central Oklahoma about what you can do if you've been impacted.
"Having access to all of that information that you could have on a credit report would be a really great way for someone to steal your identity to open up lines of credit in your name, open bank accounts in your name, open credit cards,” Kitt Letcher, president and CEO with The Better Business Bureau of Central Oklahoma, said.
And when you think about almost half the country being affected, that's a lot of impact.
The hack happened sometime between mid-May and the end of July.
In a statement Equifax said, in part:
"Criminals exploited a U.S. website application vulnerability to gain access to certain files."
They go on to say that the company has found no evidence of unauthorized activity through their core consumer or commercial credit reporting databases.
Haifeng Ji says there's no way to keep an attack like this from happening.
"Maybe it's impossible to prevent because there are some vulnerabilities on the web applications where it hasn't been discovered,” Haifeng Ji, a computer science professor at Oklahoma City Community College, said.
Some hackers find the vulnerabilities by pretending to be a real customer.
"But they actually try to steal data from the database which is linked to the website,” Ji said.
However, there are still ways you can protect yourself.
"If you have been affected, contacting Trans Union, contacting Experian, making sure that fraud risk is also alerted on your accounts there,” Letcher said.
"Checking your bank accounts on a regular basis. Check your credit cards on a regular basis. The things we talk about that seems tedious, in this instance, they're really important," Ji said.
Ji says it’s always important to keep your software on your computer up to date, and make sure your Firewall is turned on.
A breach in data and trust for millions of consumers.
Click here to see if you’ve been impacted.