Which creatures are damaged by Cure spells?

Yes, in FF12 for PS2, Holy-weak enemies are damaged by Cure spells.

I went back to my most recent save (level 64-65 at the Teleport Stone in the Nabreus Deadlands). While working my way into the Necrohol of Nabudis, I came across a Leynir, and then inside the Necrohol, I found an Oversoul; both were killed by my "Foe: holy-weak/Curaga" gambit. At first I couldn't tell if it was working; I ended up turning Libra on to watch their health meter dropping.

As for which enemies should be damaged by these spells, take a look at the Undead page on the FF wiki, which lists a total of 66 enemies that are undead (many of which are either marks, rare game, or bosses).

On further testing on my own, I have discovered the following;

Due to the class system, White Magic healing spells will only do damage to Holy-weak enemies if it comes from a White Mage. Cure spells that come from other classes will instead heal Holy-weak enemies.

This was not the case in the original PS2 Final Fantasy 12, as every character could offensively damage Holy-weak enemies with Cure spells.