June 4, 2026

A single GitHub issue could have hijacked Anthropic’s own Claude Code action and poisoned every project that uses it

Hands holding smartphone showing stock market data
Jakub Żerdzicki / Unsplash

The attack starts with a GitHub issue. Not a sophisticated one. Just an issue opened by a bot account with a carefully worded body that looks like an error message. When Claude Code’s GitHub Action picks it up for triage, it follows the instructions...