AccessDeniedException when trying to write a file in built container. Permission change in container build with 3.12.0?

[HerrDerb]

I have an application that creates dirs and writes files to the file system. In production, this directory is mounted. During test we used to write directly into the container.

With the update to 3.12.0 this seem not to be possible anymore as we get a AccessDeniedException: java.nio.file.AccessDeniedException: /home/jboss/myDir

I couldn't find any notes or commit in the release which indicates that something has changed with permission within the container build.
That is why I am asking:
Did something change concerning permission within the container build?