    public static function group($id){
        $usr = Db::result(
            sprintf("SELECT * FROM `user` WHERE `id` = '%d' OR `userid` = '%s' LIMIT 1", 
                Typo::int($id), 
                Typo::cleanX($id)
                )
            );
        return $usr[0]->group;
    }

The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.