Finally I was able to get rid off the nasty bug that sporadically occurs in Photoshop CC.
I don't know what triggers it yet but at some point you notice your brushes (most notably wet ones) are painting differently than usual. It may feels like pressure sensitivity bug (like you've too much paint on your brush) but updating wacom drivers or deleting preferences file doesn't help at all. Last time I found that texture option doesn't work right in brush controls. When turned off the brush works almost as usual but without the texture augmentation.
The solution was very simple: right click on the brush icon at top left corner -> Reset Tool.
On a longer route: