Are security patches installed automatically under a normal level account?

Since 5.0, the 64bit client is automatically installed, and used by default.

In this scenario the software is installed automatically without their cooperation.

If you need an update, it is downloaded, unpacked and installed automatically.

Updates to the game are continually released and automatically installed as the user logs in.

Like modules, skins, can be uploaded and automatically installed through the administration pages.

Ninite is a service that lets users automatically install popular applications for their operating system.

If the new port has needed dependencies on other applications or libraries, these are installed beforehand automatically.

In either case, any prerequisites/dependencies will be installed automatically by the package system, without need for manual intervention.

Maybe not necessarily automatically install, but certainly to automatically download and notify you.