CVE-2024-35225 — Jupyter Server Proxy has a reflected XSS issue in host parameter

Affected: jupyterhub jupyter-server-proxy, jupyterhub jupyter_server_proxy, jupyter_server_proxy

Jupyter Server Proxy allows users to run arbitrary external processes alongside their notebook server and provide authenticated web access to them. Versions of 3.x prior to 3.2.4 and 4.x prior to 4.2.0 have a reflected cross-site scripting (XSS) issue. The `/proxy` endpoint accepts a `host` path segment in the format `/proxy/<host>`. When this endpoint is called with an invalid `host` value, `jupyter-server-proxy` replies with a response that includes the value of `host`, without sanitization [2]. A third-party actor can leverage this by sending a phishing link with an invalid `host` value containing custom JavaScript to a user. When the user clicks this phishing link, the browser renders the response of `GET /proxy/<host>`, which runs the custom JavaScript contained in `host` set by the actor. As any arbitrary JavaScript can be run after the user clicks on a phishing link, this issue permits extensive access to the user's JupyterLab instance for an actor. Patches are included in versions 4.2.0 and 3.2.4. As a workaround, server operators who are unable to upgrade can disable the `jupyter-server-proxy` extension.

GHSA-fvcq-4x64-hqxr — Jupyter Server Proxy has a reflected XSS issue in host parameter

Affected: PyPI: jupyter-server-proxy

### Impact

There is a reflected cross-site scripting (XSS) issue in `jupyter-server-proxy`[1]. The `/proxy` endpoint accepts a `host` path segment in the format `/proxy/<host>`. When this endpoint is called with an invalid `host` value, `jupyter-server-proxy` replies with a response that includes the value of `host`, without sanitization [2]. A third-party actor can leverage this by sending a phishing link with an invalid `host` value containing custom JavaScript to a user. When the user clicks this phishing link, the browser renders the response of `GET /proxy/<host>`, which runs the custom JavaScript contained in `host` set by the actor. As any arbitrary JavaScript can be run after the user clicks on a phishing link, this issue permits extensive access to the user's JupyterLab instance for an actor. This issue exists in the latest release of `jupyter-server-proxy`, currently `v4.1.2`. **Impacted versions:** `>=3.0.0,<=4.1.2`

### Patches

The patches are included in `==4.2.0` and `==3.2.4`.

### Workarounds

Server operators who are unable to upgrade can disable the `jupyter-server-proxy` extension with:

``` jupyter server extension disable jupyter-server-proxy ```

### References

[1] : https://github.com/jupyterhub/jupyter-server-proxy/ [2] : https://github.com/jupyterhub/jupyter-server-proxy/blob/62a290f08750f7ae55a0c29ca339c9a39a7b2a7b/jupyter_server_proxy/handlers.py#L328

Most recent entries from all

CVE-2024-35225 — Jupyter Server Proxy has a reflected XSS issue in host parameter

GHSA-fvcq-4x64-hqxr — Jupyter Server Proxy has a reflected XSS issue in host parameter