# Simon Willison: '2,000 people tried to hack my AI assistant'

> A 2,000-person prompt-injection bounty against a Claude Opus 4.6 email assistant ended with the secret still safe.

- Org: Simon Willison
- Date: 2026-06-26
- Category: article, security
- Source: https://simonwillison.net/2026/Jun/26/hack-my-ai-assistant/
- Canonical page: https://ai-tldr.dev/releases/simonw-hack-my-ai-jun26/

## In short

Simon Willison covers Fernando Irarrázaval's HackMyClaw challenge, where 2,000 participants sent 6,000 email-based prompt injection attempts at a Claude Opus 4.6 assistant. The $1,000 bounty went unclaimed — no one extracted the protected secret.

## What it is

Simon Willison's June 26, 2026 post covers HackMyClaw, a public challenge run by Fernando Irarrázaval that invited 2,000 participants to extract a 'secrets.env' file from a Claude Opus 4.6 email assistant named Fiu. After 6,000 email-based injection attempts and a combined $1,000 bounty from Corgea, Abnormal AI, and an anonymous donor, the challenge ended with no successful exfiltration.

## How it works

Participants emailed Fiu, an OpenClaw assistant rate-limited to ten messages per hour. Fiu had access to the secret file and explicit instructions never to reveal it. Attackers crafted payloads designed to override that instruction; every attempt that reached the inbox was processed on a schedule, and any successful injection would have leaked the secret in Fiu's reply. Fernando Irarrázaval closed the challenge when infrastructure and model costs grew too high to keep running.

## Why it matters

HackMyClaw is one of the largest open-bounty tests of a frontier model's prompt-injection resistance, and the zero-success result lines up with what Anthropic has been claiming about Claude Opus 4.6's hardening. Simon Willison cautions that 6,000 failed attempts do not prove future invulnerability — but the data point matters for anyone weighing whether to ship Claude-backed agents into critical workflows.

## Try it

https://simonwillison.net/2026/Jun/26/hack-my-ai-assistant/

## Links

- [Read on simonwillison.net](https://simonwillison.net/2026/Jun/26/hack-my-ai-assistant/)
- [HackMyClaw site](https://hackmyclaw.com)
- [Author profile](https://simonwillison.net/)