Vibe codingHardvc-g171

Subject Ai code reviewLevel Senior–Staff~19 minCommon in Security interviewsIndustries Software development

Question

An AI added this GitHub Actions step to "comment a greeting using the PR title." It works on your test PRs. A security researcher opens a PR and runs arbitrary commands in your CI. How?

yaml

1on:2  pull_request_target:3    types: [opened]4jobs:5  greet:6    runs-on: ubuntu-latest7    steps:8      - name: Greet9        run: |10          echo "Processing PR: ${{ github.event.pull_request.title }}"11          ./scripts/post-comment.sh "${{ github.event.pull_request.title }}"

What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it — tests, edge cases, reading critically — and how you’d re-prompt or decompose to get it right.

Learn the concepts

Describe your solution

Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.

Run or narrate your approach, then ask the coach.