Eminently hackable Internet company reports 15% increase in fourth quarter revenue.

Yahoo late on Monday confirmed the completion of its sale to Verizon has been pushed back to the second quarter.

The Internet company originally expected the transaction to close during the first quarter.

"However, given work required to meet closing conditions, the transaction is now expected to close in Q2 of 2017. The company is working expeditiously to close the transaction as soon as practicable in Q2," Yahoo said, in a statement.

Verizon’s $4.83 billion (€4.50 billion) takeover of Yahoo has been complicated by the fact that Yahoo fell victim to major cyberattacks that took place before the Verizon deal was struck but weren’t disclosed until afterwards. One attack compromised the personal information of more than 500 million users, while another compromised more than 1 billion users.

Marni Walden, president of product innovation and new business at Verizon, said at a conference earlier this month that she couldn’t say with any certainty whether the deal will still definitely go ahead.

"The opportunities ahead with Verizon look bright," insisted Yahoo CEO Marissa Mayer, in a statement on Monday.

"In addition to integration planning, our top priority continues to be enhancing security for our users," she said. "With security protocols and password changes in place, approximately 90% of our daily active users have already taken or do not need to take remedial action to protect their accounts, and we’re aggressively continuing to drive this number up. Our commitment to our users is unwavering, and we continue to be encouraged by their loyalty to us and their ongoing patronage of our products."

If the deal does close, Yahoo recently announced that the parts of the company not included in the transaction will begin operating as an investment company, and its name will change to ‘Altaba’. Yahoo CEO Marissa Mayer will step down from the board.

Yahoo’s disclosure on Monday was made alongside its fourth quarter financial report.

Revenue for the final three months of 2016 surged to $1.47 billion from $1.27 billion a year ago, driven predominantly by growth in so-called ‘mavens’ (mobile, video, native and social) revenue. Traffic acquisition costs (TACs) increased to $509 million from $271 million.

Yahoo swung to an operating profit of $64 million from a year-earlier operating loss of $4.53 billion, which was largely the result of a $4.46 billion impairment charge. Net earnings came in at $162 million, compared to s $4.44 billion net loss a year ago.

"I’m very pleased with our Q4 results and incredibly proud of the team’s execution on our 2016 strategic plan, particularly given the uniquely eventful past year for Yahoo," Mayer said. "What we have achieved reflects some of the most impressive teamwork, focus, and resilience I’ve seen throughout my career."