diff --git a/keystone/credential/controllers.py b/keystone/credential/controllers.py
index 321acc4858..3ce16d92d2 100644
--- a/keystone/credential/controllers.py
+++ b/keystone/credential/controllers.py
@@ -49,7 +49,8 @@ class CredentialV3(controller.V3Controller):
                 raise exception.ValidationError(attribute='access',
                                                 target='blob')
             ret_ref = ref.copy()
-            ret_ref['id'] = hashlib.sha256(blob['access']).hexdigest()
+            ret_ref['id'] = hashlib.sha256(
+                blob['access'].encode('utf8')).hexdigest()
             # Update the blob with the trust_id, so credentials created
             # with a trust scoped token will result in trust scoped
             # tokens when authentication via ec2tokens happens
diff --git a/tests-py3-blacklist.txt b/tests-py3-blacklist.txt
index 8605b3a1ac..348847349d 100644
--- a/tests-py3-blacklist.txt
+++ b/tests-py3-blacklist.txt
@@ -1,4 +1,3 @@
 keystone.tests.unit.test_v3_auth
-keystone.tests.unit.test_v3_credential
 keystone.tests.unit.test_v3_oauth1
 keystone.tests.unit.token.test_fernet_provider