I do not have permission to view a particular project. I cannot see that project in the project list. I cannot see a particular board in the board list, when that board is part of that project. If I visit the URL of the board directly, I get a modal information div that says:
Error
The requested board cannot be viewed because it either does not exist or you do not have permission to view it.
However, beside/behind/below that div I can see the title of the board and the names of its filters.
This seems like a minor privilege bug, leaking a bit of information that shouldn't be.