Shadow Issues, Light going through walls slightly

It's not obvious to me what you are trying to show here but it doesn't look like that left corner is touching the floor, although optically that's hard to tell from a screenshot.

Ok, another example. The red light on the other side goes through the walls here, even though it is closed and the wall is 12cm thick.

What is your lighting setup? Can you give an easy replicatable example of where and when this happens? I've been using Unity for quite some time and have hardly ever had issues with shadows and those are almost always fixed by changing either light or shadow settings.