The evolved form of the parasites residing in Infested Corpses, these vile creatures are comprised entirely of maggots. Most of them appear in a waterway in the cathedral's grounds and one is found in a cell in the Irithyll Dungeon which drops the Great Magic Shield sorcery.
- Three are found by taking an alternate path to the right of the Cleansing Chapel, lurking about a shallow waterway surrounding the chapel's annex.
- Another is found a bit further, by following a narrow passage located to the right of the Ravenous Crystal Lizard's dwelling place. It guards the Poisonbite Ring.
- One is found imprisoned in a cell on the first floor of the initial cell block, roughly below the first bonfire. It drops the Great Magic Shield sorcery.
Like the other maggots enemies, Corpse Grubs inflict the maggot status with their attacks, which can be removed with a torch, or cured with a Bloodred Moss Clump. Although stronger and more aggressive than their infected hosts, they share the same weakness to fire damage and will writhe in agony if set alight.
Great Magic Shield