# CVE-2023-40170: cross-site inclusion (XSSI) of files in jupyter-server

Source: https://junglewise.ai/threats/cve-2023-40170-cross-site-inclusion-xssi-of-files-in-jupyter-server  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-08-28  
License: CC BY 4.0 with a link back

CVE-2023-40170 · Severity: low · CVSS 3.1 · Published 2023-08-28

jupyter-server is the backend for Jupyter web applications. Improper cross-site credential checks on `/files/` URLs could allow exposure of certain file contents, or accessing files when opening untrusted files via  "Open image in new tab". This issue has been addressed in commit `87a49272728` which has been included in release `2.7.2`. Users are advised to upgrade. Users unable to upgrade may use the lower performance `--ContentsManager.files_handler_class=jupyter_server.files.handlers.FilesHandler`, which implements the correct checks.

Technologies: [jupyter-server (PyPI)](https://junglewise.ai/threats/technologies/pypi-jupyter-server). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2023-40170 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-40170 being exploited in the wild.

**How severe is CVE-2023-40170?** Low severity, with a CVSS score of 3.1, published 28 August 2023.

**Which products and versions are affected?** jupyter-server (PyPI) ECOSYSTEM:introduced=0,fixed=2.7.2, GIT:introduced=0,fixed=87a4927272819f0b1cae1afa4c8c86ee2da002fd|ECOSYSTEM:introduced=0,fixed=2.7.2.

**Is there a fix for CVE-2023-40170?** Yes. jupyter-server (PyPI): upgrade to 2.7.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2023-40170?** Check whether you run jupyter-server (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- jupyter-server (PyPI): upgrade to 2.7.2 or later

  ```sh
  pip install "jupyter-server>=2.7.2"
  ```


## Affected products

- jupyter-server (PyPI) ECOSYSTEM:introduced=0,fixed=2.7.2, GIT:introduced=0,fixed=87a4927272819f0b1cae1afa4c8c86ee2da002fd|ECOSYSTEM:introduced=0,fixed=2.7.2

## Identifiers

- CVE-2023-40170
- GHSA-64x5-55rw-9974
- PYSEC-2023-157

## Related threats

- [Jupyter Server authorization bypass in kernel gateway handlers](https://junglewise.ai/threats/cve-2026-114135-jupyter-server-is-the-backend-for-jupyter-web-applications-from)
- [Jupyter Server token leakage in 5xx error logs](https://junglewise.ai/threats/cve-2026-86049-jupyter-server-token-leakage-in-5xx-error-logs)
- [Jupyter Server stored XSS in nbconvert handlers](https://junglewise.ai/threats/cve-2026-44727-jupyter-server-stored-xss-in-nbconvert-handlers)
- [Jupyter Jupyter Server CORS bypass via improper origin validation](https://junglewise.ai/threats/cve-2026-6657-jupyter-jupyter-server-cors-bypass-via-improper-origin-validation)
- [Jupyter jupyter-server path traversal in _get_os_path](https://junglewise.ai/threats/cve-2026-5422-jupyter-jupyter-server-path-traversal-in-get-os-path)