DuckDuckGo CI/CD RCE: How a Single GitHub Workflow Could Have Backdoored Every DuckDuckGo Browser — Writeup Analysis
Some vulnerabilities are interesting because of their complexity. Others are terrifying because of their simplicity. The GitHub Actions RCE reported against DuckDuckGo in 2026 falls firmly in the second category: one misconfigured workflow file, zero required privileges beyond a free GitHub account, and a straight path from a forked pull request to a poisoned release shipped inside every DuckDuckGo browser on the planet. This is my original analysis of a disclosed finding by independent researcher 6r1ff1n , reported through DuckDuckGo's HackerOne program (report #3619287 — full disclosure: https://hackerone.com/reports/3619287). What follows is my own breakdown of the technique, the attack chain, and the lessons for hunters and defenders. Analysis by Faizan Akhtar. The Discovery at a Glance In early 2026, 6r1ff1n was reviewing DuckDuckGo's public GitHub repositories when one workflow file stood out: .github/workflows/semver-label.yml in duckduckgo/content-scope-scripts — ...