Hello there!
I found one solution to light leaking through the walls and even planes, wanna share it.
Set in light source settings “Contact shadow length” to 0.1 (There could be some bugs with shadows, so you can play with its value. For me common values are 0.007, 0.05, 0.1). Also the wall should have the “Contact shadow” checked (it is by default if I’m not wrong).
Hope it will help someone!
Thanks to Munghard from Reddit for this solution
