H2O Vulnerable to Arbitrary File Overwrite

In h2oai/h2o-3 version 3.46.0, the /99/Models/{name}/json endpoint allows for arbitrary file overwrite on the target server. The vulnerability arises from the exportModelDetails function in ModelsHandler.java, where the user-controllable mexport.dir parameter is used to specify the file path for writing model details. This can lead to overwriting files at arbitrary locations on the host system.