Vulnerability · Published Jan 17, 2025 · Assigned by GitHub_M
CVE-2025-23205`frame-ancestors: self` grants all users access to formgrader in nbgrader
Medium 6.9
In plain English
A medium-severity security flaw in nbgrader from jupyter. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
nbgrader is a system for assigning and grading notebooks. Enabling frame-ancestors: 'self' grants any JupyterHub user the ability to extract formgrader content by sending malicious links to users with access to formgrader, at least when using the default JupyterHub configuration of `enable_subdomains = False`. #1915 disables a protection which would allow user Alice to craft a page embedding formgrader in an IFrame. If Bob visits that page, his credentials will be sent and the formgrader page loaded. Because Alice's page is on the same Origin as the formgrader iframe, Javasript on Alice's page has _full access_ to the contents of the page served by formgrader using Bob's credentials. This issue has been addressed in release 0.9.5 and all users are advised to upgrade. Users unable to upgrade may disable `frame-ancestors: self`, or enable per-user and per-service subdomains with `JupyterHub.enable_subdomains = True` (then even if embedding in an IFrame is allowed, the host page does not have access to the contents of the frame).
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | nbgrader | 0.9.5 | GHSA-fcr8-4r9f-r66m |
| PyPI | nbgrader | 0.9.5 | PYSEC-2026-1692 |
Affected products (as reported)
Weakness: CWE-668 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
References
- https://github.com/jupyter/nbgrader/security/advisories/GHSA-fcr8-4r9f-r66m x_refsource_CONFIRM
- https://github.com/jupyter/nbgrader/pull/1915 x_refsource_MISC
- https://github.com/jupyter/nbgrader/commit/73e137511ac1dc02e95790d4fd6d4d88dab42325 x_refsource_MISC
- https://jupyterhub.readthedocs.io/en/stable/explanation/websecurity.html#:~:text=frame-ancestors x_refsource_MISC