---
title: "Security researchers in an OpenAI bug bounty program hacked OpenAI, accessing its \"monorepo\" on GitHub, using a cybersecurity version of Opus 4.8 and Opus 5 (Robert McMillan/Wall Street Journal)"
type: signal
url: https://frontiernewswire.com/s/security-researchers-in-an-openai-bug-bounty-program-hacked-openai-8174a4bf
published: 2026-09-18T04:40:33.000Z
byline: "Source: TECHMEME"
---

# Security researchers in an OpenAI bug bounty program hacked OpenAI, accessing its "monorepo" on GitHub, using a cybersecurity version of Opus 4.8 and Opus 5 (Robert McMillan/Wall Street Journal)

Source: TECHMEME · Published 2026-09-18 · Canonical: https://frontiernewswire.com/s/security-researchers-in-an-openai-bug-bounty-program-hacked-openai-8174a4bf

Robert McMillan / Wall Street Journal : Security researchers in an OpenAI bug bounty program hacked OpenAI, accessing its "monorepo" on GitHub, using a cybersecurity version of Opus 4.8 and Opus 5 — A bug-hunting independent security research team was able to access OpenAI's internal code system, exposing growing risks in automated cyber threats

In this story: [Wall Street Journal](https://frontiernewswire.com/companies/wall-street-journal), [Claude Opus 5](https://frontiernewswire.com/models/claude-opus-5), [GitHub](https://frontiernewswire.com/companies/github), [Robert McMillan](https://frontiernewswire.com/people/robert-mcmillan)

## Sources

- [Read the original at TECHMEME](https://www.techmeme.com/260918/p1#a260918p1)

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---

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