The Rogue's Sneak Attack says
Beginning at 1st level, you know how to strike subtly and exploit a foe’s distraction. Once per turn, you can deal an extra 1d6 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use a finesse or a ranged weapon.
You don’t need advantage on the attack roll if another enemy of the target is within 5 feet of it, that enemy isn’t incapacitated, and you don’t have disadvantage on the attack roll.
So my question is can it be used to deal extra damage to objects with normal HP.
The object in question in case it matters is the Soulmonger from Tomb of Annihilation