Control: 2.4 Ensure Log Metric Filter and Alerts Exist for Project Ownership Assignments/Changes

Description

In order to prevent unnecessary project ownership assignments to users/service-accounts and further misuses of projects and resources, all roles/Owner assignments should be monitored. Members (users/Service-Accounts) with a role assignment to primitive role roles/Owner are project owners. The project owner has all the privileges on the project the role belongs to. These are summarized below:

• All viewer permissions on all GCP Services within the project
• Permissions for actions that modify the state of all GCP services within the project
• Manage roles and permissions for a project and all resources within the project
• Set up billing for a project Granting the owner role to a member (user/Service-Account) will allow that member to modify the Identity and Access Management (IAM) policy. Therefore,grant the owner role only if the member has a legitimate purpose to manage the IAM policy. This is because the project IAM policy contains sensitive access control data. Having a minimal set of users allowed to manage IAM policy will simplify any auditing that may be necessary.

Remediation

From Console

Create the prescribed log metric:

1. Go to Logging/Logs-based Metrics by visiting https://console.cloud.google.com/logs/metrics and click "CREATE METRIC".
2. Click the down arrow symbol on the Filter Bar at the rightmost corner and select Convert to Advanced Filter.
3. Clear any text and add:

(protoPayload.serviceName="cloudresourcemanager.googleapis.com")
AND (ProjectOwnership OR projectOwnerInvitee)
OR (protoPayload.serviceData.policyDelta.bindingDeltas.action="REMOVE"
AND protoPayload.serviceData.policyDelta.bindingDeltas.role="roles/owner") OR (protoPayload.serviceData.policyDelta.bindingDeltas.action="ADD"
AND protoPayload.serviceData.policyDelta.bindingDeltas.role="roles/owner")

4. Click Submit Filter. The logs display based on the filter text entered by the user.
5. In the Metric Editor menu on the right, fill out the name field. Set Units to 1(default) and the Type to Counter. This ensures that the log metric counts the number of log entries matching the advanced logs query.
6. Click Create Metric.

Create the display prescribed Alert Policy:

1. Identify the newly created metric under the section User-defined Metrics at https://console.cloud.google.com/logs/metrics.
2. Click the 3-dot icon in the rightmost column for the desired metric and select Create alert from Metric. A new page opens.
3. Fill out the alert policy configuration and click Save. Choose the alerting threshold and configuration that makes sense for the user's organization. For example, a threshold of zero(0) for the most recent value will ensure that a notification is triggered for every owner change in the project:

Set `Aggregator` to `Count`
Set `Configuration`:
- Condition: above
- Threshold: 0
- For: most recent value

4. Configure the desired notifications channels in the section Notifications.
5. Name the policy and click Save.

From Command Line

Create a prescribed Log Metric:

• Use the command: gcloud beta logging metrics create.
• Reference for Command Usage: https://cloud.google.com/sdk/gcloud/reference/beta/logging/metrics/create.

Create a prescribed Alert Policy:

• Use the command: gcloud alpha monitoring policies create.
• Reference for Command Usage: https://cloud.google.com/sdk/gcloud/reference/alpha/monitoring/policies/create.