The Bug:

The minecraft:generic.attack_knockback attribute doesn't work with wardens' sonic boom attack.

Steps to Reproduce:

• Build the setup as shown in the attachment below. setup.png
• Whilst standing on top of the diamond block, summon a warden that deals large amounts of knockback, (has its minecraft:generic.attack_knockback attribute set to a value of "10.0d").

• /summon minecraft:warden ~ ~ ~ {Attributes:[{Base:10.0d,Name:"minecraft:generic.attack_knockback"}],Brain:{memories:{"minecraft:dig_cooldown":{value:{},ttl:1200L}}}}

• Give yourself the resistance effect so that you don't die.

• /effect give @s minecraft:resistance 99999 4 true

• Switch into survival mode, stand on the opposite side of the glass wall to the warden, and constantly produce vibrations to make it become aggressive towards you.
• Wait for the warden to perform its sonic boom attack on you.
• Take note of how far you were knocked back and compare it to how far you are knocked back from a regular warden with default attributes.

Observed Behavior:

The minecraft:generic.attack_knockback attribute doesn't work with wardens' sonic boom attack.

Expected Behavior:

The minecraft:generic.attack_knockback attribute would work with wardens' sonic boom attack.