Creep through the cracks
I think it could be either:
(Other definitions for ooze that I've seen before include "Exude mud" , "Leak viscous matter" , "Mud at bottom of river" , "Seep out slowly" , "Flow out slowly or thickly" .)
'creep through the cracks' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for seep that I've seen before include "Leak gradually" , "Flow or leak slowly" , "Trickle through slowly" , "Leak through an opening" , "Of liquid, ooze slowly out" .)