# CVE-2018-19351: Jupyter Notebook XSS via untrusted notebooks

Source: https://junglewise.ai/threats/cve-2018-19351-jupyter-notebook-xss-via-untrusted-notebooks  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2018-11-18  
License: CC BY 4.0 with a link back

CVE-2018-19351 · Severity: low · CVSS 3 · Published 2018-11-18

Jupyter Notebook before 5.7.1 allows XSS via an untrusted notebook because nbconvert responses are considered to have the same origin as the notebook server. In other words, nbconvert endpoints can execute JavaScript with access to the server API. In notebook/nbconvert/handlers.py, NbconvertFileHandler and NbconvertPostHandler do not set a Content Security Policy to prevent this.

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

## Quick answers

**Is CVE-2018-19351 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2018-19351 being exploited in the wild.

**How severe is CVE-2018-19351?** Low severity, with a CVSS score of 3, published 18 November 2018.

**Which products and versions are affected?** notebook (PyPI) ECOSYSTEM:introduced=0,fixed=5.7.1, GIT:introduced=0,fixed=107a89fce5f413fb5728c1c5d2c7788e1fb17491|ECOSYSTEM:introduced=0,fixed=5.7.1.

**Is there a fix for CVE-2018-19351?** Yes. notebook (PyPI): upgrade to 5.7.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2018-19351?** Check whether you run notebook (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

- notebook (PyPI): upgrade to 5.7.1 or later

  ```sh
  pip install "notebook>=5.7.1"
  ```


## Affected products

- notebook (PyPI) ECOSYSTEM:introduced=0,fixed=5.7.1, GIT:introduced=0,fixed=107a89fce5f413fb5728c1c5d2c7788e1fb17491|ECOSYSTEM:introduced=0,fixed=5.7.1

## Identifiers

- CVE-2018-19351
- GHSA-49qr-xh3w-h436
- PYSEC-2018-17

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