DEV Community

Arina Cholee
Arina Cholee

Posted on

Self-hosted WAFs in Cloud-Native Storage Architectures: What Security Teams Need to Know

#websecurity #cybersecurity #waf #safeline

Cloud-native storage platforms are no longer hidden backend components.
They expose APIs, dashboards, and object gateways directly to users, automation tools, and CI/CD pipelines.

That also means they expose a larger attack surface.

In this hands-on guide, we’ll walk through:

  • Why cloud-native storage needs application-layer protection
  • Where a self-hosted WAF fits into modern architectures
  • A practical deployment pattern using Docker / Kubernetes
  • What security teams should actually test in production

Why Cloud-Native Storage Needs a WAF

Typical cloud-native storage stacks include:

  • REST APIs for object access
  • Web-based admin consoles
  • Metadata and control-plane services
  • Kubernetes-native deployments
  • High-volume, automated traffic

This makes them a frequent target for:

  • API abuse and enumeration
  • Injection attacks on metadata endpoints
  • Credential stuffing on admin dashboards
  • Bot-driven scraping and brute force
  • Upload-based attacks (path traversal, RCE attempts)

Traditional firewalls don’t see this traffic.
A Web Application Firewall (WAF) does.

Where a Self-hosted WAF Fits (Architecture View)

A common pattern in cloud-native storage environments looks like this:

┌──────────┐
│ Clients  │  Browsers / SDKs / CI Jobs
└────┬─────┘
     │ HTTP / HTTPS
┌────▼────────────────┐
│ Self-hosted WAF     │  ← API inspection, rate limits, bot control
└────┬────────────────┘
     │
┌────▼────────────────┐
│ Ingress / API GW    │  NGINX / Envoy / Traefik
└────┬────────────────┘
     │
┌────▼────────────────┐
│ Storage Services    │  Object / Metadata / Admin
└─────────────────────┘
Enter fullscreen mode Exit fullscreen mode

Why self-hosted instead of cloud-managed?

  • Storage metadata stays inside your infrastructure
  • No per-request or bandwidth-based pricing
  • Full control over logs, rules, and tuning
  • Easier compliance for regulated environments

What to Look for in a Self-hosted WAF (Practically)

When testing WAFs for storage platforms, focus on:

✅ API Payload Inspection

  • JSON & XML parsing
  • Parameter validation
  • Injection detection beyond signatures

✅ Behavior & Semantic Awareness

  • Can it distinguish normal API usage from abuse?
  • Does it reduce false positives on automation traffic?

✅ Container & Kubernetes Support

  • Docker Compose for quick tests
  • Kubernetes manifests or Helm charts for production

✅ Operational Visibility

  • Clear logs
  • Explainable blocks
  • Low-friction tuning

Hands-on: Deploying a Self-hosted WAF with Docker

Below is a typical local / staging setup using Docker Compose.
This pattern is commonly used to protect storage APIs or admin dashboards.

mkdir -p /data/waf
cd /data/waf
Enter fullscreen mode Exit fullscreen mode

Download the compose file:

wget https://waf.chaitin.com/release/latest/compose.yaml
Enter fullscreen mode Exit fullscreen mode

Create an environment file:

cat <<EOF > .env
SAFELINE_DIR=./safeline
IMAGE_TAG=latest
MGT_PORT=9443
POSTGRES_PASSWORD=strong-password
SUBNET_PREFIX=172.22.222
EOF
Enter fullscreen mode Exit fullscreen mode

Start the WAF:

docker compose up -d
Enter fullscreen mode Exit fullscreen mode

Once running, the management UI is available at:

https://localhost:9443
Enter fullscreen mode Exit fullscreen mode

At this point, you can place the WAF in front of:

  • Object storage APIs
  • Internal admin dashboards
  • Metadata services

Kubernetes Pattern (Cloud-Native)

In Kubernetes environments, self-hosted WAFs are typically deployed as:

  • A dedicated security gateway namespace
  • An Ingress-adjacent service
  • A reverse proxy protecting selected services

Example (conceptual):

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: storage-api
spec:
  rules:
  - host: storage.example.com
    http:
      paths:
      - path: /
        backend:
          service:
            name: waf-gateway
            port:
              number: 80
Enter fullscreen mode Exit fullscreen mode

This allows security teams to:

  • Apply rules per service
  • Rate-limit sensitive endpoints
  • Protect admin paths differently from data paths

Where SafeLine Fits in Practice

SafeLine WAF is often used in these environments because it balances:

  • Deep inspection (semantic & behavioral)
  • Ease of deployment (Docker / Kubernetes)
  • Operational clarity (UI + logs)

In storage-centric deployments, teams typically use SafeLine to:

  • Protect API endpoints against injection and abuse
  • Apply rate limits on upload/download paths
  • Challenge bot-driven traffic
  • Guard admin dashboards without blocking automation

Trade-offs (Important)

Like any self-hosted WAF:

  • You own updates and tuning
  • Initial learning is required
  • It’s not “set and forget”

For many teams, that trade-off is acceptable in exchange for control.

What to Test Before Going Live

Before enforcing blocks, run your WAF in monitoring mode and test:

  • Legitimate SDK and CI traffic
  • Bulk uploads and sync operations
  • Error handling for blocked requests
  • Latency impact under load

Look specifically for:

  • False positives on API clients
  • Rate limits affecting automation
  • Clear, explainable logs

Final Thoughts

Cloud-native storage architectures demand application-layer security.

A self-hosted WAF gives platform and security teams:

  • Visibility into real threats
  • Control over sensitive data paths
  • Flexibility to adapt protection as architectures evolve

Whether you choose SafeLine, Coraza, open-appsec, or another solution, the key is the same:

Treat your storage APIs like first-class applications — and protect them accordingly.

Top comments (0)