CVE-2024-35225

Description

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.

CVSS v3.1 Score

9.6

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

CWE-116 CWE-116

Affected Products

Vendor	Product	Versions
jupyter	jupyter_server_proxy	3.0.0 — 3.2.4
jupyter	jupyter_server_proxy	4.1.2 — 4.2.0

References

Advisories & Patches

https://github.com/jupyterhub/jupyter-server-proxy/commit/7abc9dc5bbb0b4b440548a5375261b8b8192fc22 https://github.com/jupyterhub/jupyter-server-proxy/commit/ff78128087e73fb9d0909e1366f8bf051e8ea878 https://github.com/jupyterhub/jupyter-server-proxy/security/advisories/GHSA-fvcq-4x64-hqxr https://github.com/jupyterhub/jupyter-server-proxy/commit/7abc9dc5bbb0b4b440548a5375261b8b8192fc22 https://github.com/jupyterhub/jupyter-server-proxy/commit/ff78128087e73fb9d0909e1366f8bf051e8ea878 https://github.com/jupyterhub/jupyter-server-proxy/security/advisories/GHSA-fvcq-4x64-hqxr

Other References

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

Frequently Asked Questions

What is CVE-2024-35225? +

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. It has a CVSS v3.1 base score of 9.6 (CRITICAL).

How severe is CVE-2024-35225? +

CVE-2024-35225 has a CVSS v3.1 score of 9.6 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

What products are affected by CVE-2024-35225? +

CVE-2024-35225 affects products from jupyter, specifically: jupyter_server_proxy. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-35225? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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