In h2oai/h2o-3 version 3.46.0, the endpoint for exporting models does not restrict the export location, allowing an attacker to export a model to any file in the servers file structure, thereby overwriting it. This vulnerability can be exploited to overwrite any file on the target server with a trained model file, although the content of the overwrite is not controllable by the attacker.
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize absolute path sequences such as “/abs/path” that can resolve to a location that is outside of that directory.