Microsoft SQL Server is a popular relational database management system that stores, manipulates, and retrieves data. While it is primarily used on Windows systems, there are ways to access it from a Linux environment. This article will explore how to use Impacket example scripts to access Microsoft SQL Server from Linux.

Impacket is a collection of Python classes and scripts for working with network protocols. It is useful for advanced users who need to perform penetration testing, exploit development, and other network-related tasks. Impacket supports a variety of protocols, including SMB, LDAP, and DNS, and can interact with Windows systems and services.

Prerequisites

Before we get started, there are a few things you will need to set up:

  1. A Microsoft SQL Server instance to connect to
  2. Credentials to access the SQL Server instance: If you do not have a Microsoft SQL Server instance available, you can download and install the free Express edition from the Microsoft website.

Accessing Microsoft SQL Server

Impacket provides various example scripts for interacting with Microsoft SQL Server. In this section, we will explore a few of these scripts and how to use them to access SQL Server from Linux.

mssqlclient.py

The mssqlclient.py script is a command-line interface for interacting with Microsoft SQL Server. It allows you to execute SQL queries, upload and download files, and perform other actions on a SQL Server instance. To connect to a SQL Server instance using mssqlclient.py, use the following syntax:

mssqlclient.py [domain/]username[:password]@[ip_address] [-windows-auth] [-port port_number]

Replace [domain/], [username], [password], [ip_address], and [port_number] with the appropriate values for your SQL Server instance.

Once connected, you can execute SQL queries using the query command. For example, to list all the tables in the current database, you can type the following command:

query "SELECT name FROM sys.tables"

This will execute the SQL query and display the results on the command line. If xp_cmdshell is enabled on the SQL Server, you can also run OS commands using the enable_xp_cmdshell and xp_cmdshell commands inside the mssqlclient.py shell. This can be useful for file transfers or further post-exploitation steps.

Conclusion

Using Impacket example scripts, you can easily access Microsoft SQL Server from Linux. The mssqlclient.py script provides a command-line interface for executing SQL queries and performing other actions on a SQL Server instance. You can also execute operating system commands using xp_cmdshell (if enabled), which can assist with tasks like file transfer or privilege escalation. Advanced users can interact with SQL Server and perform penetration testing, exploit development, and other network-related tasks with these tools.