diff --git a/lib/saml_authenticator.rb b/lib/saml_authenticator.rb
index b599e29..e1fc3a3 100644
--- a/lib/saml_authenticator.rb
+++ b/lib/saml_authenticator.rb
@@ -58,7 +58,10 @@ def register_middleware(omniauth)
                       idp_cert_fingerprint: GlobalSetting.try(:saml_cert_fingerprint),
                       idp_cert_fingerprint_algorithm: GlobalSetting.try(:saml_cert_fingerprint_algorithm),
                       idp_cert: setting(:cert),
-                      idp_cert_multi: setting(:cert_multi),
+                      idp_cert_multi: {
+                        signing: [setting(:cert_multi)],
+                        encryption: []
+                      },
                       request_attributes: request_attributes,
                       attribute_statements: attribute_statements,
                       assertion_consumer_service_url: SamlAuthenticator.saml_base_url + "/auth/#{name}/callback",