Configuring Binary Authorization to secure GKE clusters or Cloud Run.

Manage Enforcement Modes, Image Exemptions, and Break-Glass Procedures

Binary Authorization functions as an admission control deployment gate for Google Kubernetes Engine (GKE) and Cloud Run workloads. When a deployment request occurs, the service evaluates the container image against predefined security policies before allowing it to run. Administrators can configure policy enforcement in blocking mode to actively stop non-compliant images, or in dry-run mode during testing phases. In dry-run mode, the system allows the deployment to proceed while recording policy violations in Cloud Audit Logs so security teams can evaluate impact without disrupting operations.

To handle known software dependencies, policies can define an exempt image list containing trusted container registry paths. Any container image matching an exempt path bypasses standard verification checks and deploys immediately. For production emergencies, administrators can execute a break-glass procedure to bypass all policy enforcement for a specific cluster or deployment. The system logs every emergency override event to Cloud Audit Logs, capturing the identity of the user who initiated the bypass and the specific resource involved to ensure operational accountability.

Integrate Automated Attestation Workflows into CI/CD Pipelines

Automated pipelines secure the software supply chain by generating digital attestations before container images reach deployment environments. During the continuous integration phase in Cloud Build, the build system automatically inspects the container image against defined quality gates, such as vulnerability scan thresholds and build provenance requirements. Once the image passes these checks, the pipeline creates an attestation containing the unique image digest and cryptographically signs it using a private key.

The build pipeline stores the generated attestations inside Artifact Analysis as metadata occurrences linked directly to the image digest. When a deployment is initiated on GKE or Cloud Run, Binary Authorization intercepts the request and queries Artifact Analysis to verify that all required cryptographic signatures exist. If the image meets the required policy thresholds and contains valid signatures from designated attestors, the engine permits deployment. In addition to deploy-time checks, administrators can configure continuous validation to monitor running containers throughout their Pod lifecycle and detect policy violations that occur post-deployment.

Design and Configure Binary Authorization Policies and Attestor Infrastructure

A Binary Authorization policy defines the rules governing container deployment, including default evaluation rules, cluster-specific overrides, and platform-specific policies. Within these rules, administrators specify whether to allow all images, deny all images, or require explicit verification from trusted attestor resources. The evaluation engine validates image provenance using three core infrastructure components:

• Attestor Authority: The specific control resource referenced by admission rules to define which cryptographic signatures are required.
• Artifact Analysis Note: The centralized metadata storage location where attestations and verification records are published.
• Asymmetric Public Keys: The public keys stored as PKIX or managed in Cloud Key Management Service (Cloud KMS), such as Elliptic Curve P256 keys, used to verify the integrity of attestation signatures.

In enterprise architectures, organizations separate duties by placing attestor infrastructure, cryptographic keys, and runtime workloads into separate Google Cloud projects. To enable verification across projects, administrators grant the Attestors Verifier role (roles/binaryauthorization.attestorsVerifier) to the deployer project's service agent on the central attestor resource. For Cloud Run workloads, enforcement is applied directly through service annotations or enforced across projects using the run.allowedBinaryAuthorizationPolicies constraint. Organizations maintain baseline security by enforcing custom organization policy constraints with Common Expression Language (CEL) rules, ensuring all projects require valid attestations and approved signature algorithms.