Cis Azure Storage 5.2.2

5.2.2 Ensure immutability for Recovery Services vaults is Enabled (Automated)

Description

Immutable vaults safeguard backup data by preventing any operations that could result in the loss of recovery points. The immutable vault setting can be locked, making it irreversible and preventing malicious actors from disabling it and deleting backups.

Rationale

Enabling the immutable vault ensures that backup data is protected from unauthorized or accidental deletion. By locking the setting and making it irreversible, malicious actors are prevented from disabling the setting and deleting backups.

Impact

There is no additional cost for enabling vault immutability; however, a vault with locked immutability cannot be deleted without contacting Azure support and will incur the standard vault costs.

Audit Procedure

Audit from Azure Portal

1. Go to Recovery Services vaults.
2. From the list of vaults, ensure that the value in the Immutability column for each vault is Not locked or Locked.

Audit from Azure CLI

Run the following command to list Recovery Services vaults:

az backup vault list

For each Recovery Services vault, run the following command:

az backup vault show --resource-group <resource-group> --name <recovery-services-vault>

Ensure that under immutabilitySettings, state is set to Unlocked or Locked.

Audit from Azure Policy

If referencing a digital copy of this Benchmark, clicking a Policy ID will open a link to the associated Policy definition in Azure. If referencing a printed copy, you can search Policy IDs from this URL: https://portal.azure.com/#view/Microsoft_Azure_Policy/PolicyMenuBlade/~/Definitions

• Policy ID: d6f6f560-14b7-49a4-9fc8-d2c3a9807868
• Name: '[Preview]: Immutability must be enabled for Recovery Services vaults'

Expected Result

• In Azure Portal, the Immutability column shows Not locked or Locked for each vault
• In Azure CLI output, immutabilitySettings.state is set to Unlocked or Locked

Remediation

Remediate from Azure Portal

1. Go to Recovery Services vaults.
2. Click the name of a Recovery Services vault.
3. Under Settings, click Properties.
4. Under Immutable vault, click Settings.
5. Check the box under Enable vault immutability. Note: It is not possible to lock immutability until immutability has been enabled.
6. Click Apply.
7. If it is appropriate for your organization to lock immutability, under Immutable vault, click Settings.
8. Click the toggle under Lock immutability for this vault to set it to Locked.
9. Check the box next to Confirm locking immutability.
10. Click Apply.
11. Repeat steps 1-10 for each Recovery Services vault requiring remediation.

Remediate from Azure CLI

Run the following command to list Recovery Services vaults:

az backup vault list

For each Recovery Services vault requiring remediation, run the following command to enable vault immutability:

az backup vault update --resource-group <resource-group> --name <recovery-services-vault> --immutability-state Unlocked

Note: To lock the Recovery Services vault immutability state, the above command can be executed with --immutability-state Locked. Once enabled, this setting cannot be disabled and it will not be possible to delete the vault.

Default Value

Immutability is disabled by default on Recovery Services vaults.

References

No specific references listed for this control beyond the CIS Controls mapping.

CIS Controls

Profile

Level 1 | Automated