Description:

Periodically regenerating the storage account access keys is a best practice to enhance the security of Azure Storage Accounts. Access keys provide full access to the storage account, and regularly regenerating these keys helps mitigate the risk of key leakage, misuse, or unauthorized access to storage resources. Regeneration ensures that any compromised keys are invalidated and replaced with new ones.

Rationale: 

Regenerating storage account access keys periodically minimizes the risk of keys being compromised or exposed. Key rotation is an important security measure in the management of sensitive resources, ensuring that any potential exposure of keys does not result in long-term access to storage accounts. This practice is vital for meeting security and compliance standards such as SOC 2, HIPAA, GDPR, and NIST, which emphasize the importance of secure key management.

Impact:

 Regularly regenerating access keys can help maintain the security of the storage account. However, this action may disrupt services or applications that rely on those keys for authentication. It is important to ensure that the application or service consuming the keys is updated with the new keys after regeneration to avoid any service interruptions.

Default Value: 

Azure does not automatically regenerate storage account access keys. This must be manually configured as part of key management policies.

Pre-requisites:

  • Azure account: Ensure you have the necessary permissions to manage and regenerate storage account keys.

  • Azure Storage Account: Ensure the storage account exists.

  • Permissions: You need appropriate permissions, such as Owner or Contributor role, to regenerate access keys.

Remediation:

Manual Implementation Steps:

  1. Sign in to the Azure portal using an account with appropriate permissions.

  2. Navigate to the Azure Storage Account:

    • In the Azure portal, go to Storage accounts.

    • Select the Storage Account for which you want to regenerate access keys.

  3. Go to Access Keys settings:

    • In the Settings section of the storage account, click on Access keys under the "Security + networking" section.

  4. Regenerate Access Key:

    • You will see Key1 and Key2 listed in the access keys section.

    • Click the Regenerate button for Key1 or Key2 (you can regenerate both keys if necessary).

    • Confirm the regeneration of the access key.

  5. Update Applications or Services:

    • After regenerating the keys, ensure that all applications or services that use the access keys are updated with the new keys to avoid disruptions in service.

  6. Repeat the Process Periodically:

    • Set a reminder or create a policy to periodically regenerate access keys, based on your organization’s security policies.

Best Practices for Key Regeneration:

  • Automate Key Updates: Where possible, configure applications and services to use managed identities or Azure AD authentication instead of storage account keys to minimize dependency on key regeneration.

  • Communicate Key Changes: Ensure that relevant stakeholders and teams are informed of key changes to avoid service interruptions.

  • Monitor Key Usage: Use Azure Key Vault or other key management solutions to monitor and control the usage of storage account keys.

Backout Plan:

If you need to revert to the previous access key:

  1. Sign in to the Azure portal with appropriate permissions.

  2. Navigate to the Azure Storage Account.

  3. Go to Access Keys settings:

    • In the Settings section of the storage account, click on Access keys.

  4. Restore the Previous Key:

    • If necessary, you can regenerate the other key (Key1 or Key2) back to its original state to restore access for applications using that key.

References: