Three guys using Anthropic’s Claude hacked into OpenAI and accessed its source code for $6,500 reward

OpenAI paid a $6,500 bug bounty to Hacktron AI after three researchers used Anthropic's Claude and OpenAI's Codex to break into OpenAI's GitHub software repository and access a source code component called "Monorepo," the Wall Street Journal reported. "We're just three guys with Claude and Codex subscriptions," Hacktron AI's Mohan Pedhapati told the paper. The breach is the latest in a series of disclosed hacks involving OpenAI and Anthropic, which have both called for safety guardrails so security threats can be reviewed before models are released.

Good morning. On Fortune’s radar today: Fortune’s radar today: - Three guys hacked into OpenAI’s source code for $6,500. - New jobless claims are remarkably low. - Markets: Yay - The credit market demands a hefty risk premium for holding AI hyperscaler debt. - The Fed might have another 200 basis points of rate hikes coming. - Your phone treats you like a ‘zoo animal,’ research shows https://fortune.com/2026/09/16/america-dopamine-recession-economy-bedrotting-never-leave-home/ . ➡️ Did someone forward this email to you? If you would like to receive this information directly, every morning before the markets open in New York, sign up here . ONE BIG THING Three guys using Anthropic’s Claude hacked into OpenAI source code for $6,500 reward Another day, another AI hack. OpenAI paid $6,500—as part of its bug bounty program—to reward a company that used Anthropic’s Claude to hack into it, the WSJ reported https://www.wsj.com/tech/ai/hackers-used-anthropics-claude-to-break-into-openai-b40ba883?mod=hp lead pos2 . The hackers were able to get into OpenAI’s software repository on GitHub. There, they discovered a part of OpenAI’s source code named “Monorepo.” Sources told the WSJ that Monorepo is the company’s “secret sauce” that makes its models operate faster. “We’re just three guys with Claude and Codex subscriptions,” Mohan Pedhapati of Hacktron AI told the paper. Context: This is the latest in a long series of hacks and security breaches perpetrated by, and targeting, OpenAI and Anthropic, which have been disclosed by both companies. And both companies have called for safety guardrails to allow AI to be developed at a pace that allows humans to review security threat capabilities before models are released to the public. AI models are finding cybersecurity holes faster than they can be patched. - OpenAI’s listing delay raises stakes for SoftBank’s $50bn data centre IPO https://www.ft.com/content/6c467774-9d91-425e-a901-26db055e37ad?syn-25a6b1a6=1 - FT - Inside Microsoft and OpenAI, Worry About Damaging the Publishing Industry https://www.nytimes.com/2026/09/17/technology/microsoft-openai-publishing-industry.html - NYT MORE FROM FORTUNE The Barbie Effect: How Gap's New CEO Is Trying to Fix A Retail Giant https://www.youtube.com/watch?v=rF0t0nKH3GA | Fortune Daily Kevin Warsh, an angry Trump and Jerome Powell Déjà vu: how history is repeating itself https://fortune.com/2026/09/17/stocks-rebound-warsh-fed-rate-hike-trump-furious/ - Eva Roytburg The same algorithm Gen Z fears is managing its portfolio https://fortune.com/2026/09/18/gen-z-ai-investing-advisors-financial-planning-sports-betting/ - Catherina Gioino Data centers are swapping water for forever chemicals to keep AI cool https://fortune.com/2026/09/18/data-centers-ai-compute-pfas-forever-chemicals-water/ - Joshua Hong I tried a 4-day workweek at my company and it failed — for some of my employees https://fortune.com/2026/09/18/four-day-workweek-flexibility-optionality/ - Bjorn Reynolds Insilico Medicine’s Alex Zhavoronkov bets China and AI can deliver the drug industry’s next breakthrough https://fortune.com/2026/09/18/insilico-medicine-bets-china-and-ai-can-deliver-the-drug-industry-next-breakthrough/ - Nicholas Gordon Ed Sheeran asked Patriots owner Robert Kraft for $2 million aid donation after Macklemore was dropped from his tour for pro-Palestine comments https://fortune.com/2026/09/18/ed-sheeran-robert-kraft-aid-donation-macklemore-tour/ - Marco Quiroz-Gutierrez GOOD NEWS Jobless claims hit ‘the lowest numbers in years’ New unemployment claims are unusually low. In the week ended Sept. 12, initial jobless claims fell by 10,000 to 196,000, below the consensus expectation of 207,000 https://finance.yahoo.com/economy/policy/articles/weekly-initial-jobless-claims-continuing-191742956.html . Jefferies’ Thomas Simons called it “the lowest numbers in years.” This chart from Grace Zwemmer at Oxford Economics shows the phenomenon: Layoffs this year are far below those of the prior three years. THE MARKETS With the Fed in the rearview mirror, U.S. stocks are poised to resume rally U.S. futures were up this morning prior to the open in New York after the S&P 500 staged an impressive rise of 1.14% yesterday. The Fed’s rate hike on Wednesday—nominally bad for stocks because higher interest rates make new money harder to come by—already feels like a distant memory. Stocks rose across the board in Asia despite the Bank of Japan raising rates by 0.25% to 1.25%. Traders were probably more focused on the price of oil, which slipped slightly to $102 per barrel. The only blot on the copybook was Europe, where stocks fell, probably in reaction to a Bloomberg survey, which found that investors expect the European Central Bank to raise interest rates again before the end of the year, given that inflation in the euro area is still on the rise. - S&P 500 futures were up 0.25% this morning. The index rose 1.14% yesterday. - In Europe, the Stoxx 600 was down 0.26% in early trading and the U.K.’s FTSE 100 was down 0.65% before lunch. - Asia: South Korea’s KOSPI was up 2.66%. Japan’s Nikkei 225 was up 1.38%. India’s Nifty 50 was up 0.38%. China’s CSI 300 was up 1.06%. - Brent crude was $102 per barrel this morning, down from a peak of $105 in the previous 24 hours. - Bitcoin was at $78,262. U.S. stocks are well into their second year of meh Normally, American stocks outperform the rest of the world but ever since the beginning of 2025, the reverse has been true, Peter Oppenheimer and his team at Goldman Sachs said in a recent note. During that time, “The U.S. equity market has been the weakest of the major regions, a turnaround from the dominant trend since the financial crisis and increasing investor returns from a more geographically diversified portfolio.” CHART OF THE DAY Wall Street's risk tax on AI hyperscalers This chart demonstrates that the AI hyperscalers’ debt is more expensive for them to issue because the market sees it as riskier than bank debt, according to Apollo Global Management’s Torsten Sløk. Credit default swaps CDS on corporate debt—a type of insurance contract—offer a yield above a standard risk-free rate from the Fed. The yields on bank CDS are 40 basis points above the risk-free rate, but the yield on hyperscaler debt is 100 bps above. “What the market is repricing is hyperscaler credit fundamentals, namely a debt-financed AI capex cycle with rising leverage, negative free cash flow and uncertain payback on depreciating assets,” Sløk argues https://www.apollo.com/wealth/insights-news/insights/daily-spark/hyperscaler-cds-widening-is-not-a-dealer-inventory-story . QUOTE OF THE DAY “Well, I was wrong. I thought the Fed wouldn’t hike interest rates. But I still believe a hiking cycle could do more harm than good.” —Liz Thomas, chief market strategist at SoFi, doing something analysts rarely do: Admitting their forecast was no good, on the record. NUMBER OF THE DAY 200 bps That’s the number of basis points the Fed will now likely raise interest rates based on the historic correlation between the rate of inflation at the time of the first hike and the total number of hikes made before the central bank feels it has won its battle against rising prices. The correlation exists because, unsurprisingly, the higher inflation is, the more hikes the Fed must deliver to get it down. As Deutsche Bank’s Jim Reid said in an email, virtually no one is forecasting eight interest rate hikes in the foreseeable future. “But then when the Fed last started hiking in 2022, nobody was talking about over 400bps of hikes in the first year, with markets pricing just 200bps at the time. So, it serves as a reminder that markets have a tendency to underestimate the scale of Fed hiking cycles at the start,” he said. THE FRONT PAGES TODAY Trump Wants Putin to End the War. He May Offer Russia Business Deals First. https://www.nytimes.com/2026/09/17/us/trump-putin-russia-sanctions.html - NYT Trump tells Axios he's approaching major crossroads in Iran war https://www.axios.com/2026/09/17/trump-axios-interview-iran-war - Axios Weeks Before the Midterms, Almost Everything Is Getting More Expensive https://www.wsj.com/economy/weeks-before-the-midterms-almost-everything-is-getting-more-expensive-5b201bb5 - WSJ Venezuela nears deal to move $4bn gold reserve from London to New York https://www.ft.com/content/8f1f3047-372d-425f-bcd6-cfe9d5d4890c?syn-25a6b1a6=1 - FT BOJ Hikes Rates in Split Decision After Bessent’s Pressure https://www.bloomberg.com/news/articles/2026-09-18/boj-hikes-rates-at-fastest-pace-since-1990-as-inflation-persists - Bloomberg ONE MORE THING Your phone has isolated you like a ‘zoo animal,’ and your health is worse because of it, academics warn The majority of food is now bought through smartphones, according to new data from Visa Business and Economic Insights. The share of U.S. domestic spending online and in-app rose from 48% to 58% between 2019 and 2026, with similar jumps in the U.K., the U.A.E., Poland, Brazil, and Australia, Fortune’s Catherina Gioino reports https://fortune.com/2026/09/16/america-dopamine-recession-economy-bedrotting-never-leave-home/ . Streaming subscriptions now sit on more cards than cinema and concert spending in every market studied. It’s gotten so bad Americans are speaking roughly 28% fewer words a day than they did in 2007, a trend the researchers tied directly to the convenience economy. Regular contact with neighbors among young adults has fallen from 51% to about one in four in just over a decade. “Using the self checkout is more efficient because … you don’t have to waste time talking with the cashier,” Valeria Pfeifer, one of the researchers behind the study, told Fortune . And Americans now spend roughly 93% of their lives indoors, according to physician John La Puma, author of Indoor Epidemic. Part of that is driving brain fog, poor sleep, and chronic disease. “You’re living like a zoo animal, no horizon, stale air, in a box,” he told the Santa Barbara Independent. “That’s not burnout. It’s captivity biology.” - Would you like to sponsor this newsletter? Contact Polly Raven polly.raven@fortune.com mailto:polly.raven@fortune.com for details.