Regarding Input Sanitization during Login

[strisen]

I just recently installed Mailinabox, and noted that it installed RoundCube 1.4.7 along with it.

On the default login page from RoundCube, I am trying to understand if there is any kind of user input sanitization being performed by RoundCube itself before the data reaches the DB side. (Due to Security Concerns)

Admittedly, I am fairly new to PHP and this hasn't helped when looking in the various configuration / plugin files for any such reference.

I would greatly appreciate it if someone could point me in the right direction for this.

Thank you.