diff --git a/keystoneclient/common/cms.py b/keystoneclient/common/cms.py
index 85fa30715..1c343f68d 100644
--- a/keystoneclient/common/cms.py
+++ b/keystoneclient/common/cms.py
@@ -332,7 +332,8 @@ def cms_sign_data(data_to_sign, signing_cert_file_name, signing_key_file_name,
                                 '-inkey', signing_key_file_name,
                                 '-outform', 'PEM',
                                 '-nosmimecap', '-nodetach',
-                                '-nocerts', '-noattr'],
+                                '-nocerts', '-noattr',
+                                '-md', 'sha256', ],
                                stdin=subprocess.PIPE,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE)