Steps to reproduce

1. Create a new world, random seed, creative mode with cheats enabled.
2. /tp ~ -40 ~
3. /fill ~ ~ ~ ~20 ~20 ~5 air
4. /fill ~ ~ ~2 ~20 ~20 ~2 border_block
5. /give @s gold_block 64
6. /give @s diamond_pickaxe
7. /gamemode s
8. Stand next to the border wall, point straight at it, and try to place a gold block.
9. Move to the left, stand next to the border wall, point straight at it, and mine with the pickaxe.
10. /gamemode c
11. Break through the border wall and look at what you've done.

Expected results

Nothing happened--you cannot place blocks or break blocks on the other side of a border block wall.

Observed results

You placed the gold block and mined some blocks on the other side of the border wall while in survival mode.

Border blocks are made to protect private areas and they are allowing players outside this area break and place blocks inside it

(i tested with member players and this bug just happens below 0 layer)