AI agent incident

The ChainDrop npm worm planted hooks in Claude Code and VS Code

Reported · 2 sources

What happened

A self-propagating worm that Microsoft tracked as ChainDrop, beginning with [email protected], spread through hundreds of npm packages, stole credentials, republished malicious updates automatically, and planted hooks into Claude Code and VS Code. Reported counts of affected packages ranged from about 353 to 868.

Why it matters

Attackers targeted agent tooling directly rather than incidentally, and the credentials at risk were the non-human identities sitting in CI and package-publishing pipelines.

Sources

  1. Microsoft ChainDrop supply chain compromise: Anatomy of a self-propagating worm
  2. The Hacker News Keyv-Linked npm Worm Poisons Hundreds of Packages, Plants Claude Code and VS Code Hooks

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Background reading

Agent plugins and skills are a supply chain An explainer on the problem behind this incident.

Cite or correct this record

“The ChainDrop npm worm planted hooks in Claude Code and VS Code.” The Permission Layer AI Agent Incident Database, https://thepermissionlayer.com/incidents/chaindrop-npm-worm/. Database updated October 22, 2026.

Every record traces to the dated sources above. If something here is wrong or missing, email [email protected] and it gets fixed. See this record in the full list.

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