This is Part 4 of our AI Coding Agent Horror Stories series, a look at real security incidents involving AI coding agents, and how Docker Sandboxes keeps credentials out of an agent’s reach at the execution layer.

In Part 1, we walked through six categories of AI coding agent failures and why they keep happening. The agent runs as you, with your filesystem permissions and your credentials, and nothing sits between the model’s decision and the shell’s execution. Part 2 went deep on the rm -rf ~/ incident. Part 3 moved the same problem into a production cloud environment. The issue keeps credentials in frame but flips the questions around: instead of asking what an agent does with the secrets it holds, we ask what happens to the secrets themselves.

Today’s Horror Story: The Agent That Read Everyone’s Keys

On August 26, 2025, malicious versions of the Nx build package were published to npm. Nx draws roughly four million downloads a week, and the compromised releases carried a post-install hook pointing at a file called telemetry.js:

cat package.json