Shares of Yahoo tanked more than 6 percent Thursday after the company announced a massive data breach and media reports said Verizon might revise its pending $4.8 billion acquisition of the Internet pioneer.

Yahoo said Wednesday that in 2013 hackers stole the personal information of 1 billion users – the largest known hacking in history.

The troubling revelation came less than three months after Yahoo said it was the victim of a breach in 2014 that compromised the data of 500 million users, which was the largest breach ever before this week’s disclosure. Yahoo noted that the two hackings were unconnected and separate.

The announcement of these two attacks was dreadful timing for Yahoo.

In July, wireless carrier Verizon agreed to buy the struggling web company. Now, the terms of the deal could be changed or the acquisition could be scrapped altogether.

Sources told Bloomberg and other media outlets that Verizon is exploring a discount or exiting the deal.

Investors are pressuring the carrier to make alterations considering the severity of the attack that the White House said Thursday is being investigated by the FBI.

Verizon did not comment on if it is seeking a change beyond pointing to a statement released soon after Yahoo’s disclosure.

“As we’ve said all along, we will evaluate the situation as Yahoo continues its investigation,” a Verizon spokesperson said in a statement Wednesday. “We will review the impact of this new development before reaching any final conclusions.

“Yahoo believes the deal will go through as previously agreed. “We are confident in Yahoo's value and we continue to work toward integration with Verizon,” Yahoo said in a statement.

Yahoo stock fell 6.11 percent to close at $38.41 per share Thursday – its steepest single day decline since February. Shares of Verizon hovered around Wednesday’s close before closing up less than 1 percent to $51.82. (Anadolu Agency)

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