diff --git a/synapse/rest/well_known.py b/synapse/rest/well_known.py
index d2e500d564..0d270de8bb 100644
--- a/synapse/rest/well_known.py
+++ b/synapse/rest/well_known.py
@@ -17,6 +17,7 @@ import json
 import logging
 
 from twisted.web.resource import Resource
+from synapse.http.server import set_cors_headers
 
 logger = logging.getLogger(__name__)