Rotating Encryption Keys and Renewing Certificates

Encryption key rotation and certificate renewal are essential security practices that help mitigate the risk of compromised keys or expired certificates. AWS provides automated and manual mechanisms to rotate encryption keys and renew SSL/TLS certificates.

This study guide covers: ✔ Key Rotation vs. Certificate Renewal ✔ AWS Services for Key & Certificate Management ✔ How to Rotate Encryption Keys ✔ How to Renew SSL/TLS Certificates ✔ Best Practices & Common Mistakes ✔ SecureCart Use Case: Ensuring Continuous Data Security

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🔹 Understanding Key Rotation vs. Certificate Renewal

Process	Purpose	Frequency
Encryption Key Rotation	Prevents prolonged key exposure and ensures compliance.	Recommended annually or as per security policies.
Certificate Renewal	Ensures SSL/TLS encryption for secure communications.	Required before expiration (every 1-3 years, or auto-renewed in ACM).

📌 Why Rotate Encryption Keys? ✔ Reduces the risk of key compromise. ✔ Meets compliance requirements (PCI DSS, GDPR, HIPAA). ✔ Ensures data remains protected over time.

📌 Why Renew Certificates? ✔ Prevents downtime due to expired SSL/TLS certificates. ✔ Maintains secure encrypted connections for web applications.

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🔹 SecureCart Use Case: Protecting Payment Transactions

SecureCart, an e-commerce platform, encrypts customer payment data stored in Amazon RDS and secures web traffic using SSL/TLS certificates.

✅ SecureCart’s Security Needs: ✔ Encrypt all sensitive customer data using AWS KMS. ✔ Rotate encryption keys annually to meet PCI DSS compliance. ✔ Ensure SSL/TLS certificates do not expire to maintain secure HTTPS connections. ✔ Monitor and audit key usage using AWS CloudTrail.

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🔹 How to Rotate Encryption Keys in AWS

AWS Key Management Service (KMS) supports automatic and manual key rotation.

1️⃣ Automatic Key Rotation for AWS-Managed Keys

✔ AWS KMS automatically rotates AWS-managed keys every year. ✔ No additional configuration is required.

✅ Steps to Enable Automatic Key Rotation:

1. Navigate to AWS KMS → Select your Customer Managed Key (CMK).

2. Under Key Rotation, check Enable key rotation.

🔹 Why Use It? ✔ Hands-free management of key rotation. ✔ No impact on existing encrypted data.

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2️⃣ Manual Key Rotation for Customer Managed Keys (CMKs)

For customer-managed keys, AWS does not automatically rotate keys. Instead, you must create a new key and update all dependent applications.

✅ Steps to Manually Rotate a KMS Key:

1. Create a New Key in AWS KMS.

2. Update IAM Policies & Applications to use the new key.

3. Re-encrypt Data with the new key.

4. Schedule Deletion of the old key (after verifying all data is migrated).

🔹 Why Use It? ✔ Ensures full control over key lifecycle. ✔ Allows migration to stronger encryption algorithms.

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🔹 How to Renew SSL/TLS Certificates in AWS

AWS Certificate Manager (ACM) simplifies certificate renewal for applications using CloudFront, ALB, or API Gateway.

1️⃣ Automatic Certificate Renewal in ACM

✔ ACM automatically renews certificates before expiration. ✔ Works only for ACM-issued certificates used with CloudFront, ALB, or API Gateway.

✅ Steps to Enable Automatic Renewal:

1. Navigate to AWS Certificate Manager (ACM).

2. Select your issued SSL/TLS certificate.

3. Ensure it is attached to a CloudFront distribution, ALB, or API Gateway.

🔹 Why Use It? ✔ Prevents certificate expiration without manual intervention. ✔ Ensures HTTPS remains active for SecureCart’s checkout pages.

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2️⃣ Manual Certificate Renewal for Non-ACM Certificates

For third-party or private certificates, you must manually renew and update your AWS resources.

✅ Steps to Manually Renew a Certificate:

1. Request a new certificate from your certificate authority (CA).

2. Upload the new certificate to ACM or IAM.

3. Update CloudFront, ALB, or EC2 instances to use the new certificate.

4. Verify HTTPS connections before removing the old certificate.

🔹 Why Use It? ✔ Required if using third-party SSL providers. ✔ Allows customization of certificate authorities.

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🔹 AWS Services for Key & Certificate Management

AWS Service	Purpose
AWS KMS	Manages encryption keys & enforces key rotation.
AWS ACM	Issues & renews SSL/TLS certificates automatically.
AWS CloudTrail	Logs encryption key usage for security audits.
AWS Secrets Manager	Stores and rotates sensitive credentials.

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✅ Best Practices for Key Rotation & Certificate Renewal

✔ Enable automatic key rotation for AWS-managed keys. ✔ Manually rotate customer-managed keys annually. ✔ Monitor KMS key usage using AWS CloudTrail. ✔ Set up ACM for automatic SSL/TLS certificate renewal. ✔ Use AWS Secrets Manager for automatic credential rotation.

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⚠️ Common Mistakes & How to Avoid Them

Mistake	Impact	Solution
Not rotating encryption keys	Increased risk of key compromise	Enable key rotation in AWS KMS.
Forgetting to renew SSL/TLS certificates	HTTPS downtime, loss of trust	Use ACM for auto-renewal.
Deleting old keys before re-encrypting data	Permanent data loss	Migrate data before deleting old keys.
Not updating IAM policies after key rotation	Application failures	Update all references to new keys.

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✅ Summary

✔ Use AWS KMS key rotation to protect encrypted data. ✔ Enable automatic SSL/TLS renewal in ACM to prevent downtime. ✔ Use AWS CloudTrail to audit encryption key usage. ✔ Manually rotate customer-managed keys & update applications.