Mysql Atualizando um registro com um valor do registro anterior

UPDATE refs_table t1
  JOIN (
    SELECT RefID, @s:=IF(Status IS NULL, @s, Status) Status
      FROM (SELECT * FROM refs_table ORDER BY RefID) r,
    (SELECT @s:=NULL) t
  ) t2
  ON t1.RefID = t2.RefID
SET t1.Status = t2.Status