Villagers can be punched through walls by zombies (zombie villagers).
How to reproduce:
Create a formation like this (wall needs to be 2 or more blocks high)
w - wall
v - villager
z - zombie
z w z
w v w
z w z
Notice that the villager gets damaged and killed pretty soon.
Edit: It seems to happen only when the villager is pushed/punched towards the corners of the walls
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However, this issue has been closed as Working as Intended.
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