diff --git a/phpBB/includes/functions_user.php b/phpBB/includes/functions_user.php
index a32f14e48f..82400de932 100644
--- a/phpBB/includes/functions_user.php
+++ b/phpBB/includes/functions_user.php
@@ -3376,7 +3376,7 @@ function group_validate_groupname($group_id, $group_name)
 */
 function group_set_user_default($group_id, $user_id_ary, $group_attributes = false, $update_listing = false)
 {
-	global $cache, $db;
+	global $cache, $db, $phpbb_dispatcher;
 
 	if (empty($user_id_ary))
 	{
@@ -3472,6 +3472,11 @@ function group_set_user_default($group_id, $user_id_ary, $group_attributes = fal
 		}
 	}
 
+	$vars = array('group_id', 'user_id_ary', 'group_attributes', 'update_listing', 'sql_ary');
+	$event = new phpbb_event_data(compact($vars));
+	$phpbb_dispatcher->dispatch('core.group_set_user_default', $event);
+	extract($event->get_data_filtered($vars));
+
 	if ($update_listing)
 	{
 		group_update_listings($group_id);