S&P 500 futures fell on Wednesday night after the index snapped a nine-day win streak, as geopolitical fears remain elevated.

Futures tied to the broad market index fell by 0.5%, while Nasdaq 100 futures shed 0.7%. Dow Jones Industrial Average futures were trading near the flatline.

Shares of Broadcom traded 13% lower on Wednesday night after the chipmaker reported a fiscal second-quarter revenue miss. Cybersecurity stock CrowdStrike also fell 10% after guiding for lackluster second-quarter revenue guidance.

A pickup in U.S.-Iran tensions, and a subsequent move higher in oil prices and Treasury yields, weighed on stocks. The S&P 500 shed 0.74%, while the Nasdaq Composite fell 0.89%. The blue-chip Dow crumbed 620.72 points, or 1.21%.

Oil rose after attacks escalated between the U.S. and Iran. Iran struck Kuwait International Airport early Wednesday, while one day earlier U.S. Central Command said it had defeated multiple Iranian ballistic missiles and drones, and carried out "self-defense strikes" on Qeshm Island in the Persian Gulf. It said that this was in response to "attempted attacks" by Tehran.

The S&P 500 notched its ninth straight week of gains on Friday. But Keith Lerner, CIO and chief market strategist at Truist Wealth, noted that a sell-off is normal following such strong runs.

"I just think we're due for a rest," he said on CNBC's "Closing Bell." "We've come a long way. Fundamentals are solid. Bull market still deserves a benefit of the doubt, but often markets are two steps forward, one step back. We've had three steps forward, so maybe at least a mini step back, or at least some sideways chop."

Ciena and Brown-Forman are set to report earnings before Thursday's opening bell. Traders will also watch out for the first quarter's unit labor costs and productivity final readings, as well as initial jobless claims for the week ending May 30.

— CNBC's Kevin Brueninger contributed to this report.