@uromulou in the house!
the exposure of sensitive data is one of the most common attacks in the world, as an example, I found a website with such a problem.
https://www.hdradios.com.br/
This is the site with this type of failure, if you enter your panel here, https://www.hdradios.com.br/site-va/admin/painel.php, you will see that the user and password are already there by default, the only thing you will have to do is confirm the code and press ENTER.
Now you will see that the default data is:
login: admin@hdradios.com.br
password: 123456