How thick is the back of the cabinet ( or the bracket that goes onto the wall ) as that will take up some of the 40 mm of the screw's length.
I would not trust a mere 10 mm of screw in the wall to hold a cabinet that weighs 20 kg. Add a few more kg for the things that are put into the cabinet to get the real static load. Then consider the dynamic forces from cabinet doors pulled opened and slammed shut. These are horizontal forces pushing and pulling on the fixings.
I doubt very much that the 10 mm of plug and screw in the wall remain firm for very long. The plaster and tile will probably stop the cabinet dropping straight down put will do very little to hold it if someone pulls it away from the wall. With the cabinet door(s) open then the bottom will be pressed against the wall and the top will be pulling away from the wall.
Drill at least 20 mm into the brick work, push the plug fully into that 20 mm and then use screws long wnough to go 20 mm into the brick work
