5 Things You Must Know Before the Market Opens Friday - TheStreet

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Here are five things you must know for Friday, Sept. 23:

1. --The breach at Yahoo! (YHOO)  in 2014 is likely the largest hacking incident to occur to date as the Internet company confirmed Thursday that it affected 500 million users when a state-sponsored actor infiltrate its network. 

Yahoo! did not name the country, but said personal details stolen included names, telephone numbers, email address, dates of birth and hashed passwords. In some instances, encrypted or unencrypted security questions and answers also were breached.

The company didn't explain what took so long for it to uncover the breach, and also declined to explain how it reached its conclusions about the attack for security reasons. Yahoo! it was working with the FBI and other law enforcement.

Yahoo! began investigating a possible breach in July, around the time the tech site Motherboard reported that a hacker who uses the name "Peace" was trying to sell account information belonging to 200 million Yahoo! users, the Associated Press reported.

The theft represents the most accounts ever stolen from a single email provider, according to computer security analyst Avivah Litan of Gartner. 

"It's a shocking number," Litan told the AP. "This is a pretty big deal that is probably going to cost them tens of millions of dollars. Regulators and lawyers are going to have a field day with this one."

The breach also could have implications on the $4.8 billion sale of Yahoo!'s core business to Verizon (VZ) - Get Report

Yahoo! shares were down 1.5% in premarket trading on Friday.

2. -- The embattled CEO of Wells Fargo (WFC) - Get Report , John Stumpf, resigned from his position on the Federal Reserve's advisory council while a group of senators Thursday wrote to the Department of Labor urging officials to look into whether or not Wells Fargo violated wage and working hour laws.

Stumpf's resignation from San Francisco Fed's Federal Advisory Council was a "personal decision" by the CEO, a Wells Fargo spokeswoman said. "His top priority is leading Wells Fargo." 

The announcement came two days after Stumpf faced bipartisan outrage from a Senate panel over alleged misconduct at the bank, believed to have gone on at the second-largest U.S. bank for years. About 5,300 employees were fired and Wells Fargo was fined $185 million by U.S. and California regulators earlier this month amid a scandal over millions of accounts allegedly opened by the bank without customers' permission.

Wells Fargo is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells WFC? Learn more now.

3. -- Big ad buyers and marketers are upset with Facebook (FB) - Get Report  after learning the company vastly overestimated average viewing time for video ads on its platform for two years, The Wall Street Journal reported, citing people familiar with the situation.

Several weeks ago, Facebook disclosed in a post on its "Advertiser Help Center" that its metric for the average time users spent watching videos was artificially inflated because it was only factoring in video views of more than three seconds. The company said it was introducing a new metric to fix the problem.

Facebook is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells FB? Learn more now.

The stock fell 1.8% in premarket trading on Friday.

4. -- Iraq's oil minister said his country supports any deal to prop up oil prices in the international market ahead of next week's meeting of oil producers in Algeria, the AP reported.

Members of the Organization of the Petroleum Exporting Countries and non-OPEC producers are scheduled to meet Sept. 28 in Algeria in a bid to reach a deal to boost prices by limiting oil production. In April, oil producers met in Qatar to discuss the proposal but failed to agree on a cap after Iran, which wants to boost exports after years of sanctions, refused to join in.

In a statement issued late Thursday, Minister Jabar al-Luaibi set a production ceiling of between 4.75 and 5 million barrels per day. Al-Luaibi said Iraq's "fixed policy is to maintain Iraq's share" in the global oil market.

Oil prices in the U.S. early Friday slipped 0.5% to $46.07 a barrel. Crude oil gained 2.2% on Thursday.

5. -- U.S. stock futures were pointing lower Friday following three days of gains that were fueled by the Federal Reserve's slow-and-steady interest rate plan.

The Nasdaq closed at a record high on Thursday for the second session in a row. Click here to check out the latest technical analysis from Helene Meisler of Real Money, TheStreet's premium site for active traders (subscription required after 14-day free trial).

European stocks were trading lower Friday and Asian shares closed to the downside.

The economic calendar in the U.S. Friday includes the weekly Baker-Hughes Rig Count at 1 p.m. EDT.

Philadelphia Fed President Patrick Harker, Atlanta Fed President Dennis Lockhart and Cleveland Fed President Loretta Mester are scheduled to speak at noon in Philadelphia on a panel about the Fed's role in communities. Dallas Fed President Robert Kaplan is scheduled to speak at 12:30 p.m. EDT at the Texas Oil & Gas Association Lone Star Energy Forum, according to CNBC.

Earnings are expected Friday from Finish Line (FINL) .