To remediate this misconfiguration in GCP using GCP CLI, please follow the below steps:

1. Firstly, identify the SQL Read Replica instance that needs to be encrypted using CMKs. You can use the following command to list all the SQL instances in your GCP project:

gcloud sql instances list

2. Once you have identified the SQL Read Replica instance, you can enable encryption using the following command:

gcloud sql instances patch [INSTANCE_NAME] --backup-encryption-key [KEY_NAME] --backup-encryption-key-path [KEY_PATH]

Replace [INSTANCE_NAME] with the name of your SQL Read Replica instance, [KEY_NAME] with the name of the CMK that you want to use for encryption, and [KEY_PATH] with the path to the CMK.

For example:

gcloud sql instances patch my-sql-replica --backup-encryption-key my-cmk --backup-encryption-key-path projects/my-project/locations/global/keyRings/my-key-ring/cryptoKeys/my-cmk

3. Verify that the encryption has been enabled for the SQL Read Replica instance using the following command:

gcloud sql instances describe [INSTANCE_NAME] --format="get(settings.backupConfiguration.enabled)"

Replace [INSTANCE_NAME] with the name of your SQL Read Replica instance.

The output of the above command should be True, indicating that encryption has been enabled for the SQL Read Replica instance using CMKs.

By following the above steps, you can remediate the misconfiguration of SQL Read Replica Instances not being encrypted using Customer Managed Keys (CMKs) in GCP.

To remediate this misconfiguration for GCP using Python, you can follow the below steps:

1. First, you need to ensure that you have enabled the Cloud KMS API for your GCP project.

2. Next, you need to create a new customer-managed key (CMK) in the Cloud KMS service. You can use the following Python code to do this:

from google.cloud import kms_v1
from google.cloud.kms_v1 import enums

def create_key(project_id, location_id, key_ring_id, key_id):
    client = kms_v1.KeyManagementServiceClient()
    parent = client.key_ring_path(project_id, location_id, key_ring_id)
    purpose = enums.CryptoKey.CryptoKeyPurpose.ENCRYPT_DECRYPT
    response = client.create_crypto_key(parent, key_id, {'purpose': purpose})
    print('Created key: {}'.format(response.name))

create_key('project-id', 'global', 'my-key-ring', 'my-key-id')

3. Once you have created the CMK, you can use it to encrypt the read replica instance. To do this, you can use the google-cloud-sql Python library. First, install the library using pip:

pip install google-cloud-sql

4. Then, you can use the following Python code to encrypt the read replica instance:

from google.cloud.sql_v1beta4 import SqlInstancesServiceClient
from google.cloud.sql_v1beta4.types import SqlInstancesSetRootPasswordRequest

def encrypt_instance(project_id, instance_name, cmk_path):
    client = SqlInstancesServiceClient()
    instance_path = client.instance_path(project_id, 'us-central1', instance_name)
    request = SqlInstancesSetRootPasswordRequest()
    request.instance = instance_path
    request.root_password = 'new-root-password'
    request.encryption_config = {'kind': 'sql#encryptionConfig',
                                 'kms_key_name': cmk_path}
    response = client.instances_service.set_root_password(request)
    print('Encrypted instance: {}'.format(response.name))

encrypt_instance('project-id', 'my-instance', 'projects/project-id/locations/global/keyRings/my-key-ring/cryptoKeys/my-key-id')

In the above code, replace 'project-id' with your GCP project ID, 'my-instance' with the name of your read replica instance, and 'projects/project-id/locations/global/keyRings/my-key-ring/cryptoKeys/my-key-id' with the path to your CMK.