GHSA-243v-98vx-264h Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance

• crates.io wasmtime: < 24.0.6 → fixed in 24.0.6 • crates.io wasmtime: >= 25.0.0, < 36.0.6 → fixed in 36.0.6 • crates.io wasmtime: >= 37.0.0, < 40.0.4 → fixed in 40.0.4

Impact Wasmtime's implementation of the `wasi:http/types.fields` resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the `wasmtime-wasi-http` crate is backed by a data structure which panics when it reaches excessive capacity and this condition was not handled gracefully in Wasmtime. Panicking in a WASI implementation is a Denial of Service vector for embedders and is treated as a security vulnerability in Wasmtime. Patches Wasmtime 24.0.6, 36.0.6, 40.0.4, 41.0.4, and 42.0.0 patch this vulnerability and return a trap to the guest instead of panicking. Workarounds There are no known workarounds at this time, embedders are encouraged to update to a patched version of Wasmtime. Resources • Limitations of `http::HeaderMap`