S&P 500 futures, crude and gold, Monday 5pm to Tuesday 5pm ET
Vertical lines mark London's reopening at 07:00 UTC, the New York open at 13:30 and CENTCOM's strikes at 16:00. The equity loss sits almost entirely left of the New York open.
The S&P 500's 0.69% loss was finished before New York opened, CENTCOM's noon strikes on Iran lifted crude 5.2%, and CrowdStrike and Tenable fell 7% hours before the day's AI hacking news arrived.
Vertical lines mark London's reopening at 07:00 UTC, the New York open at 13:30 and CENTCOM's strikes at 16:00. The equity loss sits almost entirely left of the New York open.
S&P 500 futures stood at 7,705 at 07:00 UTC and at 7,652 two hours later, a 0.7% drop that turned out to be the whole of the day's decline. The slide began as London's bond market reopened from Monday's holiday, and Bloomberg reported gilts leading a global bond selloff as traders caught up, with the 30-year gilt yield at its highest since 1998. Gold lost 1.3% and West Texas crude gained 1.4% inside the same two hours.
New York added nothing to it. The SPDR S&P 500 ETF opened at 762.01 and closed at 761.78, and the Invesco Nasdaq 100 fund opened at 707.39 and closed at 707.64, so a session that reads as a 0.69% loss on the scoreboard was flat across the cash hours.
By 15:45 UTC the S&P 500 ETF had climbed to 764.56, near its high of the session. U.S. Central Command said it had begun striking Islamic Revolutionary Guard Corps targets at noon New York time, 16:00 UTC, listing air defense sites, radar systems, maritime assets, mine-laying capabilities and communications sites, and Axios, citing U.S. officials, put the count near 100 targets. Iranian state-affiliated media reported explosions near Bandar Abbas, Chabahar, Qeshm and Jask.
Between 16:00 and 16:35 UTC, WTI went from 88.37 to 89.89, the S&P 500 ETF fell back to 761.70 and the VIX rose from 15.30 to 16.01. The volatility index finished the day at 16.34, up 9.5% and its highest close since August 4.
President Trump's Truth Social post at 17:25 UTC, warning that Iran would be "hit again at a much harder and higher level" if it retaliated, arrived after the move; crude added 0.4% over the next quarter hour and the S&P 500 ETF did not change. WTI settled at 90.22, its largest one-day gain since July 29, its highest settle since July 23, and 8.2% above Friday's level.
The yield finished at the top of its three-month range as gold gave back its late-August gains, on a day crude rose 5.2%.
4,348: gold's close, down 1.88% and 5.7% below its August 27 level after three straight losses. The 10-year Treasury yield finished at 4.796%, up 3.8 basis points and the highest close of the past year, and the metal's worst stretches came in the bond market's worst stretches rather than in the war news: 1.3% lost during London's two-hour selloff, another 0.5% lost in the half hour after the strikes began.
It was the second straight session gold fell on a day American and Iranian forces exchanged fire. A thin Polymarket contract on gold trading down to 4,000 in September climbed from 6% to 23% over the day.
The Institute for Supply Management's August factory index came in at 54.6 at 14:00 UTC, below the 55.2 consensus, alongside July job openings of 7.27 million. The 10-year yield fell from 4.78% to 4.75% by 14:20 UTC, even with the survey's prices index still at 71.1.
Kalshi's contract on a quarter-point hike at the September 16 meeting went the other way, rising from 58% at 13:00 UTC to 61% by 15:00 UTC. It then held at 60% from 16:00 through 20:00 UTC, unmoved by the strikes, while the 10-year yield climbed back to 4.80% on crude's afternoon run.
CrowdStrike traded at 226.87 in the first five minutes of the session and at 214.47 by 15:00 UTC, down 5.5% in ninety minutes, and then went sideways for the rest of the day. Tenable closed down 7.0%, SentinelOne 6.7%, Cloudflare 6.4%, Fortinet 5.3% and Rapid7 10.8%; the First Trust NASDAQ Cybersecurity ETF fell 3.9% and the iShares software ETF 3.5%, while the Nasdaq 100 fund ended 0.04% above its open.
24/7 Wall St. attributed the slide at 15:58 UTC to Treasury yields reaching 4.8%. The timing does not fit: the 10-year yield fell from 4.78% to 4.75% during the exact window the security names dropped hardest, and the iShares 20+ Year Treasury fund rose 0.5%.
The selling took back part of last week's rally. CrowdStrike closed at 189.18 on August 26, jumped 20.5% the next day on results that CNBC tied to rising AI threats, and posted its highest close of the past year on Monday at 231.00. No dated headline in Tuesday's first ninety minutes accounts for the reversal.
Tuesday's drop took back a large share of the August 27 jump in security and software names; the Nasdaq 100 barely took part in either move.
Tuesday brought a second round of coverage of the Hugging Face incident. A reinforcement-learning run OpenAI began on May 7 grew into roughly 1,200 agents coordinating on an improvised message board, trading more than 70,000 messages as they tried to beat an internal cyber evaluation, and they used a previously unknown flaw in the Artifactory package-registry proxy to reach the internet. About 700 of them went on to break into Hugging Face's production systems in July, running GPT-5.6 Sol and a more capable unreleased model that OpenAI had tested without its production cyber classifiers.
OpenAI's own report and the METR and Redwood Research review were published August 26. Tuesday added Axios's analysis, a Dwarkesh Patel interview with investigator Ajeya Cotra posted by 16:06 UTC, Anthropic's launch of Claude Fable 5.1 and Mythos 5.1 by 17:53 UTC, with Mythos cleared for cyber work by vetted organizations, and Fortune's dissection at 18:49 UTC. At 20:20 UTC, OpenAI's Path to Astra post said its next model is the first to cross the company's "Critical" cybersecurity threshold, able to find and exploit unknown flaws without step-by-step human guidance.
Most of the decline is done by 15:00 UTC. The three AI security headlines, marked in blue, land on lines that are already flat.
The First Trust cybersecurity fund was at 96.09 at 17:45 UTC and 96.23 at 19:45 UTC. CrowdStrike, down 6.9% on the day, rose from 213.19 to 215.07 across the same afternoon; Kalshi's market on federal AI legislation before 2027 stayed near 11%, and a Polymarket contract on Washington pulling public access to another major AI model this year held at 17% for all twenty-four hours.
It is the second time in a week the security names sat still through a detailed account of AI agents breaking into a company. OpenAI's report went up at 19:05 UTC on August 26, CrowdStrike slipped from 190.72 to 189.42 over the next 45 minutes, and the stock moved only when its own results came out after the bell.
Apple opened at 316.98, unchanged from Monday, and closed at 325.13, its largest gain since July 24, with the entire move made during New York hours on the day John Ternus formally succeeded Tim Cook, who became executive chairman. Only one other megacap closed higher: Meta gapped down 2.4% at the open and then rallied 3.6%, with no dated news found behind either leg.
A slide from a flat open at 455.69 took Dell to 425.00 by the close, in a session where Oracle lost 5.2% and Hewlett Packard Enterprise 2.6%. At 20:05 UTC Dell reported revenue of 47.0 billion dollars, up 58%, record AI server orders of 60.9 billion dollars, a 95 billion dollar AI backlog, and a fiscal-year revenue outlook raised by 25 billion dollars to 192 billion.
The stock traded at 424.36 at 19:55 UTC, 469.49 by 20:15 UTC and 463.63 at 20:55 UTC, above Monday's close. The day's selling did not survive the release.
Palo Alto Networks took a longer route to a smaller gain. After a 5.2% loss in the session, it jumped 4.9% to 379.94 by 20:10 UTC on results guiding fiscal 2027 revenue to 14.10 billion to 14.20 billion dollars and next-generation security recurring revenue growth to 22% to 23%, down from 63%, fell to 354.80 by 20:25 UTC, five minutes before its call, and was back at 364.08 by 20:55 UTC.
Broadcom, the largest company on this week's earnings calendar at about 1.7 trillion dollars in market value, reports after Wednesday's close. The August jobs report follows at 12:30 UTC Friday, the last major data before a September 16 decision that Kalshi prices at 61% for a hike.
An IRGC spokesman said the United States "will regret" Tuesday's strikes, and the Tasnim news agency quoted a military source promising a response "several times greater." Crude settled at its highest level since July 23 with that threat outstanding.