2026年におけるクラウドネイティブセキュリティの進化

# SPIRE agent ClusterSpiffeID registration via the SPIRE Kubernetes Workload Registrar
apiVersion: spire.spiffe.io/v1alpha1
kind: ClusterSpiffeID
metadata:
  name: payment-service
spec:
  spiffeIDTemplate: "spiffe://prod.example.org/ns/{{ .PodMeta.Namespace }}/sa/{{ .PodMeta.ServiceAccountName }}"
  podSelector:
    matchLabels:
      app: payment-service
  dnsNameTemplates:
    - "payment-service.{{ .PodMeta.Namespace }}.svc.cluster.local"

# SPIRE Server configuration
server:
  default_svid_ttl: "1h"
  ca_ttl: "24h"
  ca_key_type: "ec-p384"

# .github/workflows/build.yml
jobs:
  build:
    permissions:
      id-token: write
      contents: read
      attestations: write
    steps:
      - uses: actions/checkout@v4
      - name: Build container image
        run: |
          docker build -t myapp:${{ github.sha }} .
          docker push registry.example.com/myapp:${{ github.sha }}
      
      - name: Attest build provenance
        uses: actions/attest-build-provenance@v1
        with:
          subject-name: registry.example.com/myapp
          subject-digest: sha256:${{ steps.build.outputs.digest }}
          push-to-registry: true

# Generate SBOM attached to the image
syft registry.example.com/myapp:latest \
  -o spdx-json \
  --file myapp-sbom.spdx.json

# Evaluate against CVE databases
grype sbom:myapp-sbom.spdx.json \
  --fail-on critical \
  --only-fixed

# in-toto link metadata for the "build" step
import in_toto.runlib

link = in_toto.runlib.in_toto_run(
    name="build",
    link_signing_key=signing_key,
    material_paths=["src/", "requirements.txt"],
    product_paths=["dist/app.tar.gz"],
    run_command=["python", "setup.py", "build"]
)
link.dump("build.link")

# Tetragon TracingPolicy: block shell execution from web service pods
apiVersion: cilium.io/v1alpha1
kind: TracingPolicy
metadata:
  name: prevent-shell-from-web
spec:
  kprobes:
  - call: "sys_execve"
    syscall: true
    selectors:
    - matchNamespaces:
      - namespace: production
        values: [web-service]
      matchArgs:
      - index: 0
        operator: "Equal"
        values:
        - "/bin/sh"
        - "/bin/bash"
        - "/usr/bin/python3"
        - "/usr/bin/curl"
      matchActions:
      - action: Sigkill
        argName: comm

apiVersion: cilium.io/v1
kind: CiliumNetworkPolicy
metadata:
  name: payment-service-policy
spec:
  endpointSelector:
    matchLabels:
      app: payment-service
  ingress:
  - fromEndpoints:
    - matchLabels:
        app: order-service
    toPorts:
    - ports:
      - port: "8080"
        protocol: TCP
      rules:
        http:
        - method: "POST"
          path: "/v1/charge"

# Deny containers running as root
package kubernetes.admission

deny[msg] {
  input.request.kind.kind == "Pod"
  container := input.request.object.spec.containers[_]
  not container.securityContext.runAsNonRoot == true
  msg := sprintf("Container '%v' must not run as root. Set securityContext.runAsNonRoot: true", [container.name])
}

# Require read-only root filesystem
deny[msg] {
  input.request.kind.kind == "Pod"
  container := input.request.object.spec.containers[_]
  not container.securityContext.readOnlyRootFilesystem == true
  msg := sprintf("Container '%v' must have a read-only root filesystem", [container.name])
}