When blocking a wither skull with a shield, the player still receives the wither effect

The bug

When you block a wither skull projectile with a shield, the direct impact damage is nullified but you will still receive the wither effect. Similar cases of mobs applying fire or status effects through shields have been fixed in the past.

How to reproduce

• Summon a wither with the following command:

  /summon wither ~ ~ ~ {Attributes:[{Name:generic.follow_range,Base:0}]}
  

  • This causes the wither's side heads to still attack, but the wither will stay in place and not chase you, making it easier to block its projectiles and get away from it
• Give yourself a shield and switch to survival mode
• Approach the wither and block its skulls