• Investors await key CPI data.
• Apple unveils its newest iPhones.
• The CDC approves new Covid shots.

Here are the most important news items that investors need to start their trading day:

1. Tech fizzle

The tech rebound didn't last long. The tech-heavy Nasdaq Composite fell by 1% Tuesday as Oracle shares plummeted 13.5% and other cloud stocks fell. The plunge marked Oracle's worst day in more than 20 years and it was the worst stock in the S&P 500. Apple and Adobe were also lower for the day, dropping 1.7% and nearly 4%, respectively. The S&P 500 dropped about 0.6% and the Dow Jones Industrial Average was flat. Wall Street's focus now turns toward the August consumer price index report, due Wednesday morning, as it could offer more insights about inflation. Follow live market updates.

2. New iPhones

They're here. Apple launched the anticipated iPhone 15 and iPhone 15 Plus at an event Tuesday. Those models start at $799 while the higher-end iPhone 15 Pro and Pro Max, now made with titanium, start at $999. All of them will have a USB-C charging port, a change to a universal charger from the company's proprietary Lightning charging cables used by current iPhones. The tech giant also announced a brand-new Apple Watch, made with 95% titanium and a battery life of 72 hours, and new AirPods, which will also be updated with a USB-C port.

3. Time for a boost

Updated Covid shots will be available within days. The Centers for Disease Control and Prevention on Tuesday recommended all Americans ages 6 months and older get the new vaccines from Pfizer and Moderna. The recommendation — which came from an independent panel of advisors to the agency — was issued a day after the Food and Drug Administration approved the two mRNA jabs. These shots are designed to target the omicron subvariant XBB.1.5 and come as hospitalizations for Covid-19 have increased for seven straight weeks, although still below the nationwide surge seen in summer 2022, according to the CDC.

4. BP CEO

BP Chief Executive Officer Bernard Looney resigned after less than four years in the role. The company said he was not "fully transparent in his previous disclosures" about relationships with colleagues prior to becoming CEO. Previous investigations into his relationships didn't turn up any breaches of company policy, but BP said new investigations are ongoing. Looney took over the top job at the start of the Covid-19 pandemic when energy companies' shares took a hit. U.S.-traded shares of London-based BP fell 1.3% Tuesday after climbing as much as 2.9% earlier in the session.

5. Meeting in Russia

Russian President Vladimir Putin and North Korean leader Kim Jong Un met at a space rocket launch center in Russia's far east on Wednesday for two hours of discussions. Little is known about the topics during their one-on-one meeting, but they were expected to discuss bilateral cooperation, trade and economic ties, international affairs and arms. In public remarks, Kim and Putin praised their long-standing alliance and shared perspectives. Western officials and experts have expressed concerns that Kim and Putin are negotiating what weapons North Korea could offer Russia for its war against Ukraine in exchange for Moscow offering heavily sanctioned Pyongyang much-needed food and financial assistance and, possibly, military technology. Both countries deny they were engaging in arms negotiations.

— CNBC's Hakyung Kim, Sarah Min, Alex Harring, Hayden Field, Rohan Goswami, Kif Leswing, Ashley Capoot, Annika Kim Constantino, Jesse Pound and Holly Ellyatt contributed to this report.

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