Yahoo admitted to possibly the largest data breach to date. It is reported that 500 million accounts and personal information were swiped by the hacker.

The internet company said, a state-sponsored actor performed the hacking of Yahoo's network back in 2014; which includes names, email addresses, telephone numbers, birthdays, passwords, and the security questions and its answers, Business Insider reports.

Although, sensitive financial information such as bank account numbers and credit card details were spared by the cyber culprit.

Yahoo said it is working closely with the law enforcement and is urging their users to change passwords if they haven't done it since 2014. Cybersecurity specialists advises everyone to use different passwords for each account over the internet, according to CNET.

Brett McDowell, executive director of the FIDO Alliance said, "Cybercriminals know that consumers use the same passwords across websites and applications, which is why these millions of leaked password credentials are so useful for perpetuating fraud. We need to take that ability away from criminals, and the only way to do that is to stop relying on passwords altogether," CNET added.

"The FBI is aware of the intrusion and investigating the matter," an FBI spokesperson said. "We take these types of breaches very seriously and will determine how this occurred and who is responsible. We will continue to work with the private sector and share information so they can safeguard their systems against the actions of persistent cyber criminals," CNN Money reports.

There are 1 billion monthly active users from finance to online shopping. The breach could have an effect on the on-going $4.8 billion sale of Yahoo to Verizon which is still unknown to the company. "We will evaluate, as the investigation continues, through the lens of overall Verizon interests, including consumers, customers, shareholders and related communities," Verizon said.

Yahoo notifies targeted users via their email so people can determine if they are included in the massive accounts hacked. A quick reminder is to refrain from opening junk and unknown emails which may contain encrypted messages that could steal your personal data.