<bytes::Bytes as axum_core::extract::FromRequest>::from_request would not, by default, set a limit for the size of the request body. That meant if a malicious peer would send a very large (or infinite) body your server might run out of memory and crash. This also applies to these extractors which used Bytes::from_request internally: axum::extract::Form axum::extract::Json String

axum-core has no default limit put on request bodies