The ooze can move through a space as narrow as 1 inch wide without squeezing.

A living creature that touches the ooze or hits it with a melee attack while within 5 feet of it takes 4 (1d8) necrotic damage and must succeed on a DC 13 Constitution saving throw or contract a disease. At the end of each long rest, the diseased creature must succeed on a DC 13 Constitution saving throw or its Dexterity score is reduced by 1d4. The reduction lasts until the target finishes a long rest after the disease is cured. If the disease reduces the creature’s Dexterity to 0, the creature dies and its body becomes a suppurating ooze 1d4 hours later. The disease lasts until removed by the lesser restoration spell or other similar magic.

The ooze can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.