diff --git a/x-pack/plugins/ml/server/lib/request_authorization.ts b/x-pack/plugins/ml/server/lib/request_authorization.ts
index 65676d0a5ce52..01df0900b96f4 100644
--- a/x-pack/plugins/ml/server/lib/request_authorization.ts
+++ b/x-pack/plugins/ml/server/lib/request_authorization.ts
@@ -8,6 +8,6 @@ import { KibanaRequest } from 'kibana/server';
 
 export function getAuthorizationHeader(request: KibanaRequest) {
   return {
-    headers: { authorization: request.headers.authorization },
+    headers: { 'es-secondary-authorization': request.headers.authorization },
   };
 }