Information
Ensure that all Keys in Non Role Based Access Control (RBAC) Azure Key Vaults have an expiration date set.
Rationale:
Azure Key Vault enables users to store and use cryptographic keys within the Microsoft Azure environment. The exp (expiration date) attribute identifies the expiration date on or after which the key MUST NOT be used for a cryptographic operation. By default, keys never expire. It is thus recommended that keys be rotated in the key vault and set an explicit expiration date for all keys. This ensures that the keys cannot be used beyond their assigned lifetimes.
Impact:
Keys cannot be used beyond their assigned expiration dates respectively. Keys need to be rotated periodically wherever they are used.
NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.
Solution
Remediate from Azure Portal
Go to Key vaults.
For each Key vault, click on Keys.
In the main pane, ensure that the status of the key is Enabled.
For each enabled key, ensure that an appropriate Expiration date is set.
Remediate from Azure CLI
Update the Expiration date for the key using the below command:
az keyvault key set-attributes --name <keyName> --vault-name <vaultName> --expires Y-m-d'T'H:M:S'Z'
Note:
To view the expiration date on all keys in a Key Vault using Microsoft API, the 'List' Key permission is required.
To update the expiration date for the keys:
Go to Key vault, click on Access policies.
Click on Create and add an access policy with the Update permission (in the Key Permissions - Key Management Operations section).
Remediate from PowerShell
Set-AzKeyVaultKeyAttribute -VaultName <Vault Name> -Name <Key Name> -Expires <DateTime>
Default Value:
By default, keys do not expire.