Is it possible to disable image uploading and images being cached to my server from other instances?

I have searched and not come up with the solution, I apologize if it's obvious and I have somehow missed it.

I would like to disable uploading images on my instance, and more importantly, disable the caching of images from other instances onto my server.

It's run on a tiny server, and I simply cannot afford a larger server to deal people uploading large images on instances I'm federated to being cached onto my server.

For an example, this post https://lemmy.ml/post/1450558 was federated to my server and the image was cached on my server automatically (https://lemmy.dustybeer.com/pictrs/image/19336064-e45f-4abf-b5c2-0ce7b69a1b7c.jpeg?format=webp)

It's not a big deal for a couple of images, but I can very quickly see this exploding and using up all of my (relatively tiny) disk space.

It also seems like a great vector for a malicious party to bring down an instance they don't like if they know it's caching images.

Again I apologize if I've just missed this in the docs and my searching, but any suggestions would be appreciated.