Rotating encryption keys and renewing certificates

Rotating encryption keys and renewing certificates are essential security practices that ensure continuous protection against compromised keys and expired certificates. AWS provides automated and manual mechanisms to rotate keys, manage certificates, and maintain compliance with security standards.

This study guide covers: ✔ Understanding Key Rotation vs. Certificate Renewal ✔ AWS Services for Managing Keys & Certificates ✔ How to Rotate Encryption Keys in AWS KMS ✔ How to Renew SSL/TLS Certificates in ACM ✔ Best Practices & Common Mistakes ✔ SecureCart Use Case: Securing Customer Transactions

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🔹 Understanding Key Rotation vs. Certificate Renewal

Process	Purpose	Frequency
Encryption Key Rotation	Reduces risk of key compromise by replacing encryption keys periodically.	Recommended annually or as per compliance policies.
Certificate Renewal	Ensures secure encrypted communications by replacing expiring SSL/TLS certificates.	Required before expiration (every 1-3 years or auto-renewed in ACM).

📌 Why Rotate Encryption Keys? ✔ Prevents prolonged key exposure. ✔ Ensures compliance with PCI DSS, GDPR, HIPAA. ✔ Limits the impact of a compromised key.

📌 Why Renew Certificates? ✔ Prevents service disruptions due to expired certificates. ✔ Ensures uninterrupted HTTPS encryption for applications.

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🔹 SecureCart Use Case: Securing Customer Transactions

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

✅ SecureCart’s Security Needs: ✔ Encrypt payment and customer data using AWS KMS. ✔ Rotate encryption keys annually to maintain PCI DSS compliance. ✔ Renew SSL/TLS certificates before expiration to prevent service downtime. ✔ Monitor key and certificate usage with 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 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)

AWS does not automatically rotate customer-managed keys (CMKs). 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.