[Security Issue]: Open Redirect Vulnerability in Text Generation WebUI via Gradio (CVE-2024-4940)

[2024-scable]

Describe the bug

An Open Redirect vulnerability has been identified in the text-generation-webui project. The issue stems from improper validation of the file parameter in Gradio (versions ≤ 4.36.1). This allows an attacker to redirect users to malicious external URLs. The vulnerability is tracked as CVE-2024-4940.

Bug Description

When the file parameter is supplied with an external URL, the application treats it as a valid file path without validation, leading to unintended redirection to the specified URL.

Workaround

1. Update your Gradio version

• It is important to update Gradio to the latest 4.37.1 or later, as this vulnerability can occur in Gradio versions 4.36.1 and earlier.
• To do so, use the following command: pip install gradio >= 4.37.1
  2. Validate external URLs
• We need to add external URL validation logic for values passed to the gr.File() component in the ui function. This allows us to check whether the URL is a local file path or an external URL, and block external URLs for added security.

Is there an existing issue for this?

• I have searched the existing issues

Reproduction

1. Launch the text-generation-webui.

2. Access the web interface through a browser.

3. Provide an external URL as the file parameter, such as
http://127.0.0.1:7860/file=https://google.com

4. Observe that the application redirects to the external URL (https://google.com) instead of rejecting the input.

Comment

The vulnerability arises from insufficient validation in the gr.File() component of Gradio. Specifically, the ui() function in /extensions/superbooga/script.py processes the file parameter as a local file path without validation, enabling redirection to attacker-controlled URLs.

Screenshot

Steps to reproduce the issue:

Access the interface and input an external URL:
Observe the redirection:

Logs

- File: `/extensions/superbooga/script.py` , line: 241
- Function: `ui()`

def ui():
            with gr.Tab("File input"):
                file_input = gr.File(label='Input file', type='binary')
                update_file = gr.Button('Load data')

System Info

Operating System: Windows 11 Pro
GPU Brand/Model: NVIDIA RTX 3080
Gradio Version: 4.26.0
text-generation-webui Version: latest (as of Dec 2024)