TL;DR: Fabraix is a Y Combinator Summer 2026 startup The world's frontier hacker for AI agents., currently active with a team of 2.
The world's frontier hacker for AI agents.
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Fabraix builds state-of-the-art AI red-teaming agents that continuously detect security vulnerabilities in customer-facing AI. Our product, Nyx, has already found vulnerabilities in agents at dozens of Fortune 500 companies. On AgentHarm, the leading benchmark for offensive AI security, Nyx achieved a 78% attack success rate, compared with 67% for GPT-5.6 Sol. AI agents can change more often than teams can test them. A new model, prompt, tool, permission, or data source can change what an agent does, even when the application code stays the same. And AI is also increasing how much software companies produce and how often it changes. We built Nyx to automate the work required to red-team AI agents. It is built around three capabilities: - Nyx draws on more than 10,000 jailbreaks that we ha…
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Yes. Fabraix was funded by Y Combinator in the Summer 2026 batch. The world's frontier hacker for AI agents.
Fabraix builds state-of-the-art AI red-teaming agents that continuously detect security vulnerabilities in customer-facing AI. Our product, Nyx, has already found vulnerabilities in agents at dozens of Fortune 500 companies. On AgentHarm, the leading benchmark for offensive AI security, Nyx achieved a 78% attack succe…
Fabraix was part of Y Combinator's Summer 2026 batch.
Fabraix has a team of 2 people according to Y Combinator's directory.
Fabraix is currently listed as Active with a team of 2 in Y Combinator's directory.
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