GitHub Actions CI/CD Logic Flaw: Untrusted PR Code Triggers Privileged Production Deployment via Build/Deploy Workflow Misconfiguration

Vulnerability Overview Title: Untrusted pull request code can trigger privileged production deployment Description: This vulnerability exists within the CI/CD pipeline of GitHub Actions. An attacker can leverage a logical flaw between the build workflow and the deploy workflow by creating a branch named and initiating a Pull Request (PR), thereby deploying malicious code to the production environment. Specific Steps: 1. The attacker forks the repository. 2. Creates a branch named within the forked repository. 3. Modifies the code on that branch (e.g., adds a harmless marker). 4. Initiates a Pull Request from to . 5. Waits for the build workflow to complete. 6. The deploy workflow is triggered, checking out the commit SHA of the branch as the checkout ref, rather than checking out the trusted branch. 7. The deploy workflow builds and pushes the Docker image to GHCR, triggering the Dokploy deployment workflow. 8. Ultimately, the deployed site or pushed image contains the malicious code from the unmerged Pull Request. Scope of Impact Affected Versions: 1.0.0 Fixed Version: 1.0.1 CVSS Score: 9.5/10 (Critical) Attack Vector: Network Attack Complexity: Low Attack Requirements: Present Required Privileges: None User Interaction: None Confidentiality Impact: High Integrity Impact: High Availability Impact: High Remediation Fixed Version: Upgrade to version 1.0.1. Recommended Measures: Ensure that the deploy workflow checks out code from a trusted branch (such as ) rather than the Pull Request branch when checking out. Additionally, restrict PR permissions to prevent unauthorized code deployment. POC Code main attacker-fork:main upstream:main Impact Production Supply Chain Compromise: An attacker can deploy arbitrary site code without merge approval. In affected deployments, this allows malicious JavaScript injection, credential phishing attacks, and other means to compromise production release artifacts. Container Image Pollution: Since the workflow also pushes images as , attackers can pollute the container images consumed by the deployment infrastructure.

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GitHub Actions CI/CD Logic Flaw: Untrusted PR Code Triggers Privileged Production Deployment via Build/Deploy Workflow Misconfiguration

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