BlueHat Asia: Exploiting the pipeline: Real-world CI/CD vulnerabilities and how to secure them

Description

In this BlueHat Asia, Harish Poornachander (Security Engineer at NetApp and MSRC Most Valuable Researcher 2024) breaks down how common CI/CD misconfigurations can turn build pipelines into an attacker’s execution path, and what to do about it. Covering real-world patterns seen across modern DevSecOps stacks, Harish walks through “poisoned pipeline execution” (direct and indirect) and shows how risky defaults and workflow design choices in tools like GitHub Actions can lead to code execution and secret exfiltration, especially when untrusted pull request content is allowed to run in privileged contexts. You’ll learn about practical failure modes, including: ➤Untrusted PR execution (e.g., pull_request_target pitfalls and unsafe checkouts) ➤Unsanitized inputs (branch names, PR titles, comments) that lead to command injection ➤Issue comment–driven workflows that accidentally provide “CLI access” to commenters ➤Artifact poisoning in downstream workflows (and why extraction paths matter) ➤Self-hosted runner risks (ephemeral vs. non-ephemeral) and persistence concerns ➤Privilege escalation via workflow_run ➤TOCTOU approval gaps (checking out head_ref vs. a pinned commit SHA) ➤Approval/merge bypass gotchas involving bot identities (including Dependabot scenarios) Harish closes with clear, actionable mitigations: least privilege tokens, manual approvals, commit SHA pinning, branch protections, safer artifact handling, and operational monitoring, plus quick notes on similar patterns in Azure DevOps, CircleCI, and AWS CodeBuild.