Control: 1.8 Ensure that Separation of duties is enforced while assigning service account related roles to users
Description
It is recommended that the principle of 'Separation of Duties' is enforced while assigning service-account related roles to users
The built-in/predefined IAM role Service Account admin
allows the user/identity to create, delete, and manage service account(s). The built-in/predefined IAM role Service Account User
allows the user/identity (with adequate privileges on Compute and App Engine) to assign service account(s) to Apps/Compute Instances.
Separation of duties is the concept of ensuring that one individual does not have all necessary permissions to be able to complete a malicious action. In Cloud IAM - service accounts, this could be an action such as using a service account to access resources that user should not normally have access to.
Remediation
No user should have Service Account Admin
and Service Account User
roles assigned at the same time. Removal of a role should be done based on the business requirements.
From Console
- Login to GCP Admin/IAM.
- For any member having both
Service Account Admin
andService account User
roles granted/assigned as shown in theRole
column, remove either role from the member.
Usage
Run the control in your terminal:
powerpipe control run gcp_compliance.control.cis_v130_1_8
Snapshot and share results via Turbot Pipes:
powerpipe loginpowerpipe control run gcp_compliance.control.cis_v130_1_8 --share
SQL
This control uses a named query:
with users_with_roles as ( select distinct split_part(member_entity, ':', 2) as user_name, project, _ctx, p ->> 'role' as assigned_role from gcp_iam_policy, jsonb_array_elements(bindings) as p, jsonb_array_elements_text(p -> 'members') as member_entity where split_part(member_entity, ':', 1) = 'user'),account_admin_users as( select user_name, project from users_with_roles where assigned_role = 'roles/iam.serviceAccountAdmin'),account_users as( select user_name, project from users_with_roles where assigned_role = 'roles/iam.serviceAccountUser')select distinct user_name as resource, case when user_name in (select user_name from account_users) and user_name in (select user_name from account_admin_users) then 'alarm' else 'ok' end as status, case when user_name in (select user_name from account_users) and user_name in (select user_name from account_admin_users) then user_name || ' assigned with both Service Account Admin and Service Account User roles.' else user_name || ' not assigned with both Service Account Admin and Service Account User roles.' end as reason , project as projectfrom users_with_roles;