Local File Inclusion in JSON component in gradio-app/gradio

Vulnerability Description

A local file inclusion vulnerability exists in the JSON component of gradio-app/gradio version 4.25. The vulnerability arises from improper input validation in the `postprocess()` function within `gradio/components/json_component.py`, where a user-controlled string is parsed as JSON. If the parsed JSON object contains a `path` key, the specified file is moved to a temporary directory, making it possible to retrieve it later via the `/file=..` endpoint. This issue is due to the `processing_utils.move_files_to_cache()` function traversing any object passed to it, looking for a dictionary with a `path` key, and then copying the specified file to a temporary directory. The vulnerability can be exploited by an attacker to read files on the remote system, posing a significant security risk.

References

• https://huntr.com/bounties/39889ce1-298d-4568-aecd-7ae40c2ca58e
• https://github.com/gradio-app/gradio/commit/ee1e2942e0a1ae84a08a05464e41c8108a03fa9c