diff --git a/src/userdirectory.js b/src/userdirectory.js
index 398aae893..5dbed1dac 100644
--- a/src/userdirectory.js
+++ b/src/userdirectory.js
@@ -312,7 +312,7 @@ async function start() {
     });
 
     debug(`starting server on port ${constants.USER_DIRECTORY_LDAPS_PORT}`);
-    await util.promisify(gServer.listen.bind(gServer))(constants.USER_DIRECTORY_LDAPS_PORT, '0.0.0.0');
+    await util.promisify(gServer.listen.bind(gServer))(constants.USER_DIRECTORY_LDAPS_PORT, '::');
 }
 
 async function stop() {