[Linkpost] “Three Hackers used Opus 5 to Hack Into OpenAI’s Core Codebase [WSJ]” by Linch

This is a link post.

Three whitehack hackers from Hacktron used Claude Opus 5 within hours of release to chain exploits into hacking to OpenAI's monorepo codebase.

This likely means they have access to almost all of OpenAI's research and production code, though likely not the literal model weights. Oops.

You can so their blog post about it here. Interesting sidenote: they used less than $3000 of compute credits for the entire hack.

Alternative title: OpenAI unilaterally implements "Total Research Transparency" from Plan A.

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First published:
September 17th, 2026

Source:
https://www.lesswrong.com/posts/274BMCYj2BFES2FsZ/three-hackers-used-opus-5-to-hack-into-openai-s-core

Linkpost URL:
https://www.wsj.com/tech/ai/hackers-used-anthropics-claude-to-break-into-openai-b40ba883

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Narrated by TYPE III AUDIO.