Best Practices for Container Security

Posted on by uplatzblog

Best Practices for Container Security

  • As part of the “Best Practices” series by Uplatz

 

Welcome to another installment of the Uplatz Best Practices series — equipping you to build secure, scalable, cloud-native systems.
 Today’s topic: Container Security — a must-have discipline in every DevSecOps pipeline.

🧱 What is Container Security?

Container Security focuses on protecting containerized applications throughout their lifecycle — from development and image creation to runtime and orchestration.

Containers are isolated, lightweight, and portable — but they also introduce risks:

  • Vulnerable images

  • Misconfigured containers

  • Weak secrets management

  • Escalation into the host or other containers

Security must be baked in at every layer.

✅ Best Practices for Container Security

Here’s how to secure containers across build, deploy, and runtime stages — without slowing down development.

1. Use Minimal, Trusted Base Images

📦 Start from Scratch or Alpine Where Possible – Smaller footprint, fewer vulnerabilities
 🔐 Use Verified Images from Trusted Registries – Avoid “latest” or unscanned sources
 📅 Pin Image Versions for Predictability – No surprises in prod

2. Scan Images for Vulnerabilities

🔍 Integrate Image Scanning into CI/CD (e.g., Trivy, Clair, Grype)
 ⚠️ Fail Builds with Critical CVEs
 🧪 Scan Regularly, Not Just at Build Time

3. Avoid Running Containers as Root

🚫 Drop Root Privileges Using USER in Dockerfiles
 🔐 Use Kubernetes PodSecurity Standards or PSPs
 🔒 Restrict Host Access and Capabilities

4. Use Read-Only File Systems

📁 Mount Filesystems as Read-Only When Possible
 📦 Avoid Writing to /tmp or /var/lib Without Need
 🧱 Separate Data Volumes from Core Containers

5. Manage Secrets Securely

🔐 Use Secrets Managers (Vault, KMS, Sealed Secrets)
 🧾 Avoid Embedding Secrets in Images or Env Files
 🔍 Audit Secret Access and Rotate Frequently

6. Set Resource Limits and Quotas

⚖️ Define CPU and Memory Limits for All Containers
 🚫 Prevent DoS via Resource Abuse
 🛑 Avoid Running Without Limits in Shared Clusters

7. Enforce Network Isolation

🌐 Use Kubernetes Network Policies – Limit pod-to-pod communication
 🛡 Segment Services into Trust Boundaries
 🔌 Disable Unnecessary Ports and Protocols

8. Enable Runtime Protection

👀 Use Runtime Threat Detection (e.g., Falco, Sysdig)
 📦 Block Unauthorized Processes or Connections
 📊 Monitor File System, Syscalls, Network Behavior

9. Keep Your Container Stack Updated

📅 Patch Images Regularly – Base images, app layers, dependencies
 📦 Keep Docker, Kubernetes, and Container Runtimes Updated
 🔍 Subscribe to CVE Feeds for Your Stack

10. Audit and Log Everything

📋 Log Container Lifecycle Events (Start, Stop, Fail, etc.)
 🔐 Capture Auth Attempts and Network Access Logs
 📊 Centralize Logs for Security Analytics and Compliance

💡 Bonus Tip by Uplatz

Containers move fast — so must your security.
 Treat container security as code, just like your infrastructure and pipelines.
 Automate, monitor, and never trust defaults.

🔁 Follow Uplatz to get more best practices in upcoming posts:

  • DevSecOps and Secure Pipelines

  • Kubernetes Security Policies

  • Zero Trust for Containerized Workloads

  • Runtime Threat Detection Tools

  • Securing Multi-Tenant Clusters
     …and 50+ more on cloud, DevOps, AI, and platform architecture.