hole in wall

Basically what it says on the tin. The drainage pipe for my washing machine is sitting loosely in a hole in the kitchen wall (see picture). This feels like it's risking damp getting in and causing mould. My question is, what's best to seal it with? Expanding foam? Some sort of sealing/grout...

How do I repair this hole in a wall? I’ve done some research and watched a few videos, but can someone here tell me what to do? It’s a very old house, and this pic used to be a old fireplace.