컨테이너 이미지 보안 스캐닝 실전 가이드 — Trivy, Grype, CI/CD 통합

Trivy 설치 (macOS / Linux / Docker)
# macOS (Homebrew)
brew install trivy

# Linux (apt)
sudo apt-get install wget apt-transport-https gnupg lsb-release
wget -qO - https://aquasecurity.github.io/trivy-repo/deb/public.key | sudo apt-key add -
echo deb https://aquasecurity.github.io/trivy-repo/deb $(lsb_release -sc) main | sudo tee -a /etc/apt/sources.list.d/trivy.list
sudo apt-get update
sudo apt-get install trivy

# Docker로 실행 (설치 없이)
docker run --rm aquasec/trivy image nginx:latest

Trivy 기본 스캔 명령
# 기본 스캔
trivy image nginx:latest

# 심각도 필터 (CRITICAL, HIGH만)
trivy image --severity CRITICAL,HIGH nginx:latest

# JSON 출력 (파이프라인 연동용)
trivy image --format json --output result.json nginx:latest

# CI에서 CRITICAL 발견 시 exit 1 반환
trivy image --exit-code 1 --severity CRITICAL nginx:latest

# .trivyignore로 특정 CVE 무시
echo "CVE-2023-XXXXX" >> .trivyignore
trivy image --ignorefile .trivyignore nginx:latest

# 로컬 빌드 이미지 스캔
docker build -t myapp:latest .
trivy image myapp:latest

Grype 사용 예시 (Syft SBOM 조합)
# Grype 설치
curl -sSfL https://raw.githubusercontent.com/anchore/grype/main/install.sh | sh -s -- -b /usr/local/bin

# 직접 이미지 스캔
grype nginx:latest

# Syft로 SBOM 생성 후 Grype 스캔
syft nginx:latest -o spdx-json > sbom.spdx.json
grype sbom:./sbom.spdx.json

.github/workflows/docker-security.yml
name: Docker Security Scan

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  build-and-scan:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Build image
        run: docker build -t myapp:${{ github.sha }} .

      - name: Run Trivy vulnerability scanner
        uses: aquasecurity/trivy-action@master
        with:
          image-ref: myapp:${{ github.sha }}
          format: sarif
          output: trivy-results.sarif
          severity: CRITICAL,HIGH
          exit-code: '1'

      - name: Upload SARIF to GitHub Security tab
        uses: github/codeql-action/upload-sarif@v3
        if: always()
        with:
          sarif_file: trivy-results.sarif

      - name: Push to registry (only if scan passed)
        if: success()
        run: |
          docker tag myapp:${{ github.sha }} ghcr.io/${{ github.repository }}:latest
          docker push ghcr.io/${{ github.repository }}:latest

멀티스테이지 빌드 예시 (Node.js)
# 빌드 스테이지
FROM node:20-alpine AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
RUN npm run build

# 런타임 스테이지 — 빌드 도구 제외
FROM node:20-alpine AS runtime
WORKDIR /app

# 비root 사용자 생성 및 적용
RUN addgroup -S appgroup && adduser -S appuser -G appgroup
COPY --from=builder --chown=appuser:appgroup /app/dist ./dist
COPY --from=builder --chown=appuser:appgroup /app/node_modules ./node_modules

USER appuser
EXPOSE 3000
CMD ["node", "dist/index.js"]