Fast money starts right now live in the NASDAQ market site overlooking New York

City's Times Square.

I'm Melissa Lear.

Traders on the desk are Tim Seymour, Carter Worth, Steve Brasso, and Guyadami.

Tonight on Fast Tesla tanks, the stock having its worst day in five years after CEO

Elon Musk gets sued by the SEC for fraud but Musk is fighting back will it be a

win for shareholders plus despite the odds a retail rally holding strong through the third quarter but the chart master here says Despite the Facebook under attack again. The social media giant saying 50 million users were

affected by a security flaw. Let's get to Josh Lipton in San Francisco who's

got the details on this developing story. Josh.

Mal here's what we know

Facebook saying that on Tuesday its engineers uncovered a security issue

impacting almost 50 million accounts

CEO Mark Zuckerberg

explaining that issue on a call. Take a listen.

I'm glad that we found this and that we were able to fix the vulnerability and

secure the accounts but it it definitely is an issue that this happened in the

first place and I think that this underscores the attacks that that our community and our service face and the need to keep on investing

heavily in security.

Facebook says that the investigation is still in its early stages, but that they've fixed the vulnerability

and informed law enforcement, including the FBI, saying they've yet to determine whether these accounts

were misused or any information was accessed.

So how did this attack actually work?

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