Cordyceps GitHub Actions Flaw Enabled CI/CD Pipeline Hijacking

Researchers at Novee disclosed Cordyceps, a class of systemic software supply chain flaws in GitHub Actions workflows that can let attackers hijack build and release pipelines through insecure trust-boundary crossings in CI/CD YAML configurations. The attack chains combine issues such as command injection, broken authentication logic, artifact poisoning, and privilege escalation across multiple workflows rather than a single misconfiguration. Novee said exploitation may require only a pull request or even a pull request comment from a free GitHub account, allowing low-privilege or unauthenticated attackers to execute malicious code, steal credentials, and potentially gain control of code repositories and connected cloud environments.

After scanning roughly 30,000 high-impact repositories, Novee flagged 654 projects and verified more than 300 as fully exploitable. Confirmed impact included repositories tied to Microsoft, Google, Apache, Cloudflare, and the Python Software Foundation, with examples including Azure Sentinel, Google adk-samples, Apache Doris, Black, and Cloudflare Workers tooling. The researchers said affected organizations have fixed the disclosed issues, but warned that AI coding agents are helping spread the same insecure CI/CD patterns across ecosystems including npm, PyPI, crates, and Go.