Gradio is an open-source Python package designed for quick prototyping. Starting in version 4.16.0 and prior to version 6.6.0, Gradio applications running outside of Hugging Face Spaces automatically enable "mocked" OAuth routes when OAuth components (e.g. `gr.LoginButton`) are used. When a user visits `/login/huggingface`, the server retrieves its own Hugging Face access token via `huggingface_hub.get_token()` and stores it in the visitor's session cookie. If the application is network-accessible, any remote attacker can trigger this flow to steal the server owner's HF token. The session cookie is signed with a hardcoded secret derived from the string `"-v4"`, making the payload trivially decodable. Version 6.6.0 fixes the issue.
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Fri, 27 Feb 2026 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Gradio is an open-source Python package designed for quick prototyping. Starting in version 4.16.0 and prior to version 6.6.0, Gradio applications running outside of Hugging Face Spaces automatically enable "mocked" OAuth routes when OAuth components (e.g. `gr.LoginButton`) are used. When a user visits `/login/huggingface`, the server retrieves its own Hugging Face access token via `huggingface_hub.get_token()` and stores it in the visitor's session cookie. If the application is network-accessible, any remote attacker can trigger this flow to steal the server owner's HF token. The session cookie is signed with a hardcoded secret derived from the string `"-v4"`, making the payload trivially decodable. Version 6.6.0 fixes the issue. | |
| Title | Gradio: Mocked OAuth Login Exposes Server Credentials and Uses Hardcoded Session Secret | |
| Weaknesses | CWE-522 CWE-798 |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-02-27T21:40:57.917Z
Reserved: 2026-02-18T00:18:53.963Z
Link: CVE-2026-27167
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Status : Received
Published: 2026-02-27T22:16:22.820
Modified: 2026-02-27T22:16:22.820
Link: CVE-2026-27167
No data.
OpenCVE Enrichment
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