Cloud Security Best Practices for AWS, Azure, and GCP
GeokHub
Contributing Writer
Before diving into configurations, it’s essential to understand how security responsibilities are divided in the cloud.
- Cloud Provider (AWS, Azure, GCP): Responsible for securing the infrastructure itself—data centers, networking, and physical hardware.
- Customer (You): Responsible for securing data, identities, and configurations inside your cloud environment.
Many breaches occur when customers assume providers handle everything. In reality, misconfigured storage buckets, exposed keys, or excessive privileges often lead to data leaks.
Identity and Access Management (IAM) & Least Privilege
IAM is often called the “front door” of the cloud. A weak or overly permissive IAM setup is a hacker’s dream.
- Follow Least Privilege: Grant only the permissions a role or user needs. Avoid blanket
AdministratorAccessorOwnerroles. - Use Role-Based Access Control (RBAC): Group permissions by role, not individual accounts.
- Enable MFA Everywhere: Especially for root/admin accounts.
- Rotate Keys & Credentials: Never hardcode credentials in source code or scripts. Use Secrets Manager, Key Vault, or Secret Manager instead.
- Service Accounts: Restrict what automated processes can do and avoid using them for manual work.
Tip: Regularly audit IAM policies with built-in tools like AWS IAM Access Analyzer or Azure Privileged Identity Management (PIM).
Logging, Monitoring, and Continuous Visibility
You can’t secure what you can’t see. Proper logging and monitoring is crucial for detecting suspicious activity.
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Enable Cloud-Native Logging:
- AWS → CloudTrail and GuardDuty
- Azure → Monitor and Defender for Cloud
- GCP → Cloud Audit Logs and Security Command Center
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Centralize Logs: Use a SIEM (Splunk, Datadog, Elastic) to aggregate data.
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Set Alerts: Configure alerts for unusual patterns like mass data downloads, privilege escalations, or access from unknown geographies.
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Log Retention: Store logs in immutable storage for at least 90 days (or longer if compliance requires).
Infrastructure as Code (IaC) and Configuration Checks
Most cloud setups today are provisioned with Infrastructure-as-Code (Terraform, CloudFormation, Bicep). Misconfigurations here can scale bad security practices across environments.
- Use Policy as Code: Tools like Terraform Sentinel, OPA (Open Policy Agent), or Azure Policy can enforce compliance at deployment time.
- Automated Scanning: Tools like Checkov, tfsec, or Snyk IaC catch insecure defaults before they reach production.
- Version Control: Store all IaC in Git to track changes and support rollbacks.
- Secrets in IaC: Never commit secrets to repositories. Instead, reference secure vaults.
- Continuous Validation: Integrate IaC scans into your CI/CD pipelines.
Additional Best Practices Across AWS, Azure, and GCP
While the shared model, IAM, logging, and IaC form the foundation, here are a few extra steps that pay off big:
- Network Segmentation: Use VPCs, VNets, and subnets to separate sensitive workloads.
- Encryption by Default: Encrypt data at rest (KMS, Azure Key Vault, Cloud KMS) and in transit (TLS).
- Patch Management: Keep VMs, containers, and serverless runtimes up to date.
- Zero Trust Principles: Verify identity and device posture before granting access.
- Pen Testing & Red Teaming: Simulate attacks to discover misconfigurations.
Quick Cloud Security Checklist (2025)
- ✅ Enforce least privilege IAM with MFA
- ✅ Enable centralized logging and alerts
- ✅ Encrypt data at rest and in transit
- ✅ Scan IaC templates before deployment
- ✅ Apply network segmentation and zero trust
- ✅ Regularly review misconfiguration reports
Final Thoughts
Cloud security is less about complex firewalls and more about disciplined configuration. The biggest risks aren’t nation-state hackers — they’re open buckets, leaked keys, and excessive permissions.
By mastering IAM, enabling visibility, and treating your infrastructure as code with proper validation, you dramatically reduce the chances of a costly breach.
