Cloud Security for AWS, Azure & GCP: Enterprise Guide 2025

☁️ Cloud Provider Comparison (Security Features 2025)

🔐 IAM Best Practices (Universal)

1. Least Privilege Access

• AWS: Use IAM policies with conditions, avoid wildcards (*)
• Azure: Azure RBAC with custom roles, avoid Owner/Contributor
• GCP: Predefined roles over primitive roles, use conditions

2. Multi-Factor Authentication (MFA)

• AWS: Enable MFA on root account + all IAM users
• Azure: Entra ID conditional access policies
• GCP: 2-Step Verification for all accounts

3. Service Accounts (Not User Accounts)

• AWS: Use IAM roles for EC2/Lambda, not access keys
• Azure: Managed identities for Azure resources
• GCP: Service accounts with workload identity

🔒 Data Encryption Checklist

Encryption at Rest

• ✅ Enable by default on ALL storage (S3, Azure Blob, GCS)
• ✅ Use customer-managed keys (CMK) for sensitive data
• ✅ Rotate encryption keys annually
• ✅ Enable encryption for databases (RDS, Cosmos DB, Cloud SQL)

Encryption in Transit

• ✅ TLS 1.3 minimum for ALL connections
• ✅ Disable HTTP, enforce HTTPS only
• ✅ Use VPN/PrivateLink for internal traffic

🛡️ Network Security Configuration

AWS Security Groups

# Bad Practice - Open to world
Inbound: 0.0.0.0/0 on port 22 (SSH)

# Good Practice - Restricted source
Inbound: 203.0.113.0/24 on port 22 (SSH)
Inbound: sg-12345678 on port 3306 (MySQL from app tier only)

Azure Network Security Groups

• Default-deny all inbound traffic
• Use Application Security Groups (ASG) for logical grouping
• Enable NSG flow logs for monitoring

GCP Firewall Rules

• Use tags for organizing firewall rules
• Implement hierarchical firewall policies
• Enable VPC Flow Logs

📊 Cloud Security Monitoring

AWS

• CloudTrail: Log ALL API calls
• GuardDuty: Threat detection (ML-powered)
• Security Hub: Centralized security findings
• Config: Track configuration changes

Azure

• Microsoft Defender for Cloud: CSPM + threat protection
• Azure Monitor: Log aggregation
• Sentinel: SIEM (security information event management)

GCP

• Security Command Center: Unified security dashboard
• Cloud Logging: Centralized logs
• Chronicle: Security analytics platform

💰 Cost-Effective Security Strategies

1. Use Native Tools First - AWS GuardDuty cheaper than third-party SIEM
2. Right-Size Security - Don't over-provision WAFs/firewalls
3. Automate Everything - Infrastructure as Code (Terraform, CloudFormation)
4. Use Savings Plans - Commit to security tools for 30-50% discount

🔗 Essential Tools

• Secure API Key Generator
• Password Generator