Atakujący z tym uprawnieniem mógłby zniszczyć wersję KMS. Aby to zrobić, najpierw musisz dezaktywować klucz, a następnie go zniszczyć:
# pip install google-cloud-kmsfrom google.cloud import kmsdefdisable_key_version(project_id,location_id,key_ring_id,key_id,key_version):"""Disables a key version in Cloud KMS."""# Create the client.client = kms.KeyManagementServiceClient()# Build the key version name.key_version_name = client.crypto_key_version_path(project_id, location_id, key_ring_id, key_id, key_version)# Call the API to disable the key version.client.update_crypto_key_version(request={'crypto_key_version': {'name': key_version_name, 'state': kms.CryptoKeyVersion.State.DISABLED}})defdestroy_key_version(project_id,location_id,key_ring_id,key_id,key_version):"""Destroys a key version in Cloud KMS."""# Create the client.client = kms.KeyManagementServiceClient()# Build the key version name.key_version_name = client.crypto_key_version_path(project_id, location_id, key_ring_id, key_id, key_version)# Call the API to destroy the key version.client.destroy_crypto_key_version(request={'name': key_version_name})# Example usageproject_id ='your-project-id'location_id ='your-location'key_ring_id ='your-key-ring'key_id ='your-key-id'key_version ='1'# Version number to disable and destroy# Disable the key versiondisable_key_version(project_id, location_id, key_ring_id, key_id, key_version)# Destroy the key versiondestroy_key_version(project_id, location_id, key_ring_id, key_id, key_version)
KMS Ransomware
W AWS możliwe jest całkowite ukradzenie klucza KMS poprzez modyfikację polityki zasobów KMS i zezwolenie tylko na użycie klucza przez konto atakującego. Ponieważ takie polityki zasobów nie istnieją w GCP, nie jest to możliwe.
Jednak istnieje inny sposób na przeprowadzenie globalnego KMS Ransomware, który obejmowałby następujące kroki:
Utwórz nową wersję klucza z materiałem klucza importowanym przez atakującego
from google.cloud import kmsimport base64defencrypt_symmetric(project_id,location_id,key_ring_id,key_id,plaintext):"""Encrypts data using a symmetric key from Cloud KMS."""# Create the client.client = kms.KeyManagementServiceClient()# Build the key name.key_name = client.crypto_key_path(project_id, location_id, key_ring_id, key_id)# Convert the plaintext to bytes.plaintext_bytes = plaintext.encode('utf-8')# Call the API.encrypt_response = client.encrypt(request={'name': key_name, 'plaintext': plaintext_bytes})ciphertext = encrypt_response.ciphertext# Optional: Encode the ciphertext to base64 for easier handling.return base64.b64encode(ciphertext)# Example usageproject_id ='your-project-id'location_id ='your-location'key_ring_id ='your-key-ring'key_id ='your-key-id'plaintext ='your-data-to-encrypt'ciphertext =encrypt_symmetric(project_id, location_id, key_ring_id, key_id, plaintext)print('Ciphertext:', ciphertext)
cloudkms.cryptoKeyVersions.useToSign
import hashlibfrom google.cloud import kmsdefsign_asymmetric(project_id,location_id,key_ring_id,key_id,key_version,message):"""Sign a message using an asymmetric key version from Cloud KMS."""# Create the client.client = kms.KeyManagementServiceClient()# Build the key version name.key_version_name = client.crypto_key_version_path(project_id, location_id, key_ring_id, key_id, key_version)# Convert the message to bytes and calculate the digest.message_bytes = message.encode('utf-8')digest ={'sha256': hashlib.sha256(message_bytes).digest()}# Call the API to sign the digest.sign_response = client.asymmetric_sign(name=key_version_name, digest=digest)return sign_response.signature# Example usage for signingproject_id ='your-project-id'location_id ='your-location'key_ring_id ='your-key-ring'key_id ='your-key-id'key_version ='1'message ='your-message'signature =sign_asymmetric(project_id, location_id, key_ring_id, key_id, key_version, message)print('Signature:', signature)
cloudkms.cryptoKeyVersions.useToVerify
from google.cloud import kmsimport hashlibdefverify_asymmetric_signature(project_id,location_id,key_ring_id,key_id,key_version,message,signature):"""Verify a signature using an asymmetric key version from Cloud KMS."""# Create the client.client = kms.KeyManagementServiceClient()# Build the key version name.key_version_name = client.crypto_key_version_path(project_id, location_id, key_ring_id, key_id, key_version)# Convert the message to bytes and calculate the digest.message_bytes = message.encode('utf-8')digest ={'sha256': hashlib.sha256(message_bytes).digest()}# Build the verify request and call the API.verify_response = client.asymmetric_verify(name=key_version_name, digest=digest, signature=signature)return verify_response.success# Example usage for verificationverified =verify_asymmetric_signature(project_id, location_id, key_ring_id, key_id, key_version, message, signature)print('Verified:', verified)
