NEW YORK (CNNMoney.com) -- Security software firm McAfee Inc. said Wednesday that its chairman and CEO George Samenuk would step down following an internal investigation in the ever-widening options backdating scandal, sending its shares soaring.

McAfee (Charts) shares surged over 4 percent in early trade on the New York Stock Exchange.

Making the announcement early Wednesday, McAfee also said it will need to restate historical financial results due to past stock option grants, and that the restatement will fall in the range of $100 million to $150 million.

The Santa Clara, Calif.-based company also fired Kevin Weiss as company president and said Dale Fuller will serve as interim Chief Executive Officer and president.

Samenuk, after serving almost six years at McAfee, said his decision to step down was in the "best interests of the company, its shareholders and employees."

"I regret that some of the stock option problems identified by the Special Committee occurred on my watch," Samenuk said in a prepared statement issued early Wednesday.

In related news, the co-founder and CEO of CNET Networks Inc. (down $0.64 to $9.26, Charts) Shelby Bonnie also announced his resignation early Wednesday after the company partially blamed him for backdating of stock options.

The company, which reviews consumer electronics on the Web, also said its general counsel and head of human resources have also resigned.

The Wall Street Journal reported early Wednesday two high-profile directors at Apple Inc. (down $0.10 to $73.71, Charts) may have had a conflict of interest when they conducted a investigation into the company's backdated stock options grants.

To date, about 120 companies are either under scrutiny by the government or have launched internal investigations into their options practices. But Brocade Communications (up $0.17 to $28.97, Charts) and Comverse Technologies (Charts) remain the only firms to receive criminal indictments against their top execs.

Civil suits thrive in backdating scandal