Securing Container Registry with Harbor

Overview

Harbor is an open-source container registry that provides security features including vulnerability scanning (integrated Trivy), image signing (Notary/Cosign), RBAC, content trust policies, replication, and audit logging. Securing Harbor involves configuring these features to enforce image provenance, prevent vulnerable image deployment, and maintain registry access control.

When to Use

• When deploying or configuring securing container registry with harbor capabilities in your environment
• When establishing security controls aligned to compliance requirements
• When building or improving security architecture for this domain
• When conducting security assessments that require this implementation

Prerequisites

• Harbor 2.10+ installed (Helm or Docker Compose)
• TLS certificates for HTTPS
• Trivy scanner integration
• OIDC/LDAP for authentication
• Kubernetes cluster (for deployment target)

Workflow

Step 1: Install Harbor with Security Configuration

# harbor-values.yaml for Helm deployment
expose:
  type: ingress
  tls:
    enabled: true
    certSource: secret
    secret:
      secretName: harbor-tls
      notarySecretName: harbor-tls
  ingress:
    hosts:
      core: harbor.example.com
      notary: notary.example.com

externalURL: https://harbor.example.com

persistence:
  enabled: true
  resourcePolicy: "keep"

harborAdminPassword: "<strong-password>"

trivy:
  enabled: true
  gitHubToken: "<github-token>"
  severity: "CRITICAL,HIGH,MEDIUM"
  autoScan: true

notary:
  enabled: true

core:
  secretKey: "<32-char-secret>"

database:
  type: external
  external:
    host: postgres.example.com
    port: "5432"
    username: harbor
    password: "<db-password>"
    sslmode: require

helm repo add harbor https://helm.getharbor.io
helm install harbor harbor/harbor -f harbor-values.yaml -n harbor --create-namespace

Step 2: Configure Vulnerability Scanning Policies

# Enable auto-scan on push (via Harbor API)
curl -k -X PUT "https://harbor.example.com/api/v2.0/projects/myproject" \
  -H "Authorization: Basic $(echo -n admin:Harbor12345 | base64)" \
  -H "Content-Type: application/json" \
  -d '{
    "metadata": {
      "auto_scan": "true",
      "severity": "critical",
      "prevent_vul": "true",
      "reuse_sys_cve_allowlist": "true"
    }
  }'

Step 3: Configure Content Trust

# Enable content trust at project level
curl -k -X PUT "https://harbor.example.com/api/v2.0/projects/myproject" \
  -H "Authorization: Basic $(echo -n admin:Harbor12345 | base64)" \
  -H "Content-Type: application/json" \
  -d '{
    "metadata": {
      "enable_content_trust": "true",
      "enable_content_trust_cosign": "true"
    }
  }'

# Sign image with Cosign
cosign sign --key cosign.key harbor.example.com/myproject/myapp:v1.0.0

# Verify signature
cosign verify --key cosign.pub harbor.example.com/myproject/myapp:v1.0.0

Step 4: Configure RBAC and Project Isolation

# Create project with private visibility
curl -k -X POST "https://harbor.example.com/api/v2.0/projects" \
  -H "Authorization: Basic $(echo -n admin:Harbor12345 | base64)" \
  -H "Content-Type: application/json" \
  -d '{
    "project_name": "production",
    "metadata": {
      "public": "false",
      "auto_scan": "true",
      "prevent_vul": "true",
      "severity": "high"
    }
  }'

# Harbor roles: ProjectAdmin, Maintainer, Developer, Guest, LimitedGuest
# Add member with specific role
curl -k -X POST "https://harbor.example.com/api/v2.0/projects/production/members" \
  -H "Authorization: Basic $(echo -n admin:Harbor12345 | base64)" \
  -H "Content-Type: application/json" \
  -d '{
    "role_id": 3,
    "member_user": {"username": "developer1"}
  }'

Step 5: Configure Immutable Tags and Retention

# Create tag immutability rule (prevent overwriting release tags)
curl -k -X POST "https://harbor.example.com/api/v2.0/projects/production/immutabletagrules" \
  -H "Authorization: Basic $(echo -n admin:Harbor12345 | base64)" \
  -H "Content-Type: application/json" \
  -d '{
    "tag_filter": "v*",
    "scope_selectors": {
      "repository": [{"kind": "doublestar", "decoration": "repoMatches", "pattern": "**"}]
    }
  }'

# Configure retention policy (keep last 10 tags, delete untagged after 7 days)
curl -k -X POST "https://harbor.example.com/api/v2.0/retentions" \

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