Well this particular project this comment thread is about does not actually implement any cryptographic operations, those are all done by libsodium[1] a project

Well this particular project this comment thread is about does not actually implement any cryptographic operations, those are all done by libsodium[1] a project written in C. Imagine now it is possible to construct an argument to those libsodium functions that satisfies the constraints of the Rust wrappers, but still manages to crash libsodium and execute some part of the argument, which is not unheard of since libsodium is written in C and it operates on blobs of data. Now the only mistake the implementor of thrussh has to make is to allow for that input to be passed into the rust libsodium wrapper through the protocol implementation. [1] https://github.com/jedisct1/libsodium https://github.com/jedisct1/libsodium