A werewolf from the MM has the following in its stat block:
Damage Immunities: Bludgeoning, Piercing, And Slashing Damage From Nonmagical Weapons That Aren't Silvered
And as established in the errata, unarmed strikes aren't weapons.
Weapons (p. 149). Unarmed strike doesn’t belong on the Weapons table.
Melee Attacks (p. 195). The rule on unarmed strikes should read as follows: “Instead of using a weapon to make a melee weapon attack, you can use an unarmed strike: a punch, kick, head-butt, or similar forceful blow (none of which count as weapons). On a hit, an unarmed strike deals bludgeoning damage equal to 1 + your Strength modifier. You are proficient with your unarmed strikes.”
And confirmed by Jeremy Crawford
Addressing a nuance in the PH errata: the rule lets melee weapon attacks use unarmed strikes, despite those strikes not being weapons.
Does this mean my fighter, who doesn't have a magical or silvered weapon can, instead, punch a werewolf in the face for 4 damage?