lacework-global-295
Enforce Separation of Duties While Assigning Key Management Service (KMS) Related Roles to Users (Manual)
This rule has been changed to manual, see Manual Policies for CIS GCP 2.0.0 for details.
Profile Applicability
• Level 2
Description
Best practices recommend enforcing the principle of Separation of Duties while assigning KMS related roles to users.
Rationale
The built-in/predefined IAM role Cloud KMS Admin
allows the user/identity to create, delete, and manage service account(s).
The built-in/predefined IAM role Cloud KMS CryptoKey Encrypter/Decrypter
allows the user/identity (with adequate privileges on concerned resources) to encrypt and decrypt data at rest using an encryption key(s).
The built-in/predefined IAM role Cloud KMS CryptoKey Encrypter
allows the user/identity (with adequate privileges on concerned resources) to encrypt data at rest using an encryption key(s).
The built-in/predefined IAM role Cloud KMS CryptoKey Decrypter
allows the user/identity (with adequate privileges on concerned resources) to decrypt data at rest using an encryption key(s).
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 KMS, this could be an action such as using a key to access and decrypt data a user should not normally have access to. Separation of duties is a business control typically used in larger organizations, meant to help avoid security or privacy incidents and errors. It is considered best practice.
No user(s) should have Cloud KMS Admin
and any of the Cloud KMS CryptoKey Encrypter/Decrypter
, Cloud KMS CryptoKey Encrypter
, Cloud KMS CryptoKey Decrypter
roles assigned at the same time.
Impact
Removed roles should be assigned to another user based on business needs.
Audit
From Console:
- Go to
IAM & Admin/IAM
by visiting: https://console.cloud.google.com/iam-admin/iam - Ensure no member has the roles
Cloud KMS Admin
and any of theCloud KMS CryptoKey Encrypter/Decrypter
,Cloud KMS CryptoKey Encrypter
,Cloud KMS CryptoKey Decrypter
assigned.
From Command Line:
- List all users and role assignments:
gcloud projects get-iam-policy PROJECT_ID
- Ensure that there are no common users found in the member section for roles
cloudkms.admin
and any one ofCloud KMS CryptoKey Encrypter/Decrypter
,Cloud KMS CryptoKey Encrypter
,Cloud KMS CryptoKey Decrypter
Remediation
From Console:
- Go to
Identity and Access Management (IAM) & Admin/IAM
using https://console.cloud.google.com/iam-admin/iam. - For any member having
Cloud KMS Admin
and any of theCloud KMS CryptoKey Encrypter/Decrypter
, Cloud KMSCryptoKey Encrypter
,Cloud KMS CryptoKey Decrypter
roles granted/assigned, click theDelete Bin
icon to remove the role from the member.
Use business requirements to guide removing a role.
References
https://cloud.google.com/kms/docs/separation-of-duties
Additional Information
Users granted with Owner (roles/owner) and Editor (roles/editor) have privileges equivalent to Cloud KMS Admin
and Cloud KMS CryptoKey Encrypter/Decrypter
. To avoid misuse, grant Owner and Editor roles to a very limited group of users. Use of these primitive privileges should be minimal. Separate recommendations address these requirements.