Designing management and rotation of secrets for workloads (for example, database access credentials, API keys, IAM access keys, AWS KMS customer managed keys)

What are the benefits of rotating secrets such as database credentials and API keys?

Rotating secrets limits the amount of time a secret is valid, thus reducing the window of opportunity for an unauthorized user or compromised system to access your resources. It also helps in complying with security best practices and regulatory requirements, enabling a more robust and secure infrastructure.

Can you describe the steps you would take to rotate a secret in AWS Secrets Manager?

To rotate a secret in AWS Secrets Manager, you would:

• Configure the secret to enable rotation by selecting an AWS Lambda rotation function or creating a new one.
• Set the rotation interval, or trigger rotation manually when necessary.
• The Lambda rotation function will then automatically create a new version of the secret, test the new credentials, and switch the active version to the new credentials.

What strategies can be employed for zero-downtime secret rotation?

Zero-downtime secret rotation involves using dual versions of credentials during the rotation process, where applications can use either the old or new secret for a grace period. Additionally, staggered rotation, where only a fraction of instances rotate at a time, and instantiating new resources with the rotated secrets while gracefully retiring the old ones, can help achieve zero-downtime.

Explain how IAM access keys can be automatically rotated using AWS services such as AWS Lambda and IAM?

IAM access keys can be rotated by leveraging a Lambda function that periodically triggers based on a schedule set in Amazon EventBridge. The function uses the IAM SDK to generate new access keys, update the application with the new keys, and deactivate or delete the old keys. The application must be designed to retrieve the keys securely, possibly through environment variables or encrypted storage.

How does the AWS KMS customer managed key (CMK) rotation process work?

AWS KMS supports automatic rotation of customer managed keys. Once enabled, KMS will automatically rotate the keys every year by generating new cryptographic material. It maintains the old material so that historical data is still accessible. You can also manually rotate keys by creating a new CMK and updating any applications or services to use the new CMK.

What is the importance of secret versioning in secret management?

Secret versioning allows the storage of multiple versions of a secret, with each version having unique identifiers. It’s fundamental for seamless rotation and management, providing a means to transition between different secrets without service interruption and to maintain access to encrypted data through different versions of a key.

When designing a system, how can you ensure applications don’t fail during secret rotations?

To ensure applications don’t fail during secret rotations, implement a fallback mechanism to use the previous version of a secret in case the new version is not immediately available or fails. Applications should also be designed to handle the update of secrets dynamically, without requiring a restart or redeployment, and they should be capable of retrying failed connections with a back-off strategy.

What role do permissions play in secret management and rotation?

Proper permissions are essential to grant entities the necessary privileges to access the secrets they require, but no more, in keeping with the principle of least privilege. This minimizes the risk of unauthorized access to sensitive information. Permissions must also allow for rotating secrets, which typically involves creating, retrieving, and deactivating secrets without exposing the secret itself.

How do you audit the rotation of secrets?

Auditing the rotation of secrets can be done through AWS CloudTrail, which logs all actions taken by AWS Secrets Manager and AWS KMS. You would set up proper logging and monitoring of these logs for any activity related to your secrets to ensure that rotations are happening as expected and to detect any unauthorized access attempts.

Can you explain the concept of using short-term credentials vs long-term credentials for workload security?

Short-term credentials, such as those provided by AWS Security Token Service (STS), are temporary and expire after a set duration, reducing the risk if they’re compromised. Long-term credentials, such as IAM user access keys, don’t expire by default and thus carry a higher risk. Using short-term credentials provides enhanced security due to their limited lifespan and automatic expiration.

Discuss a strategy to maintain access to encrypted data when rotating AWS KMS keys.

To maintain access to encrypted data when rotating AWS KMS keys, you enable automatic rotation for a customer managed CMK. The old cryptographic material that was used to encrypt data is retained so that you can decrypt the data even after rotation. If you create a new CMK manually, you must re-encrypt the data with the new key or retain the old key in a disabled state to decrypt data encrypted with it.

What is a key alias in AWS KMS, and how does it help in the rotation of customer managed keys?

A key alias is a friendly name that points to a CMK in AWS KMS. Using aliases allows you to reference keys in your applications without using the actual key ID. This means when you rotate a key, you simply update the key alias to point to the new CMK, while application code remains unchanged, thus streamlining the rotation process and minimizing the need for code modifications.