# CVE-2019-10255: PYSEC-2026-647 - Open Redirect vulnerability in jupyterhub and notebook

Source: https://junglewise.ai/threats/cve-2019-10255-open-redirect-vulnerability-in-jupyterhub-and-notebook  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-02  
License: CC BY 4.0 with a link back

CVE-2019-10255 · Severity: low · CVSS 3 · Published 2026-07-02

Open Redirect vulnerability in jupyterhub and notebook

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

## Quick answers

**Is CVE-2019-10255 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2019-10255 being exploited in the wild.

**How severe is CVE-2019-10255?** Low severity, with a CVSS score of 3, published 2 July 2026.

**Which products and versions are affected?** jupyterhub (PyPI) ECOSYSTEM:introduced=0,fixed=0.9.6; notebook (PyPI) ECOSYSTEM:introduced=0,fixed=5.7.8.

**Is there a fix for CVE-2019-10255?** Yes. jupyterhub (PyPI): upgrade to 0.9.6 or later; notebook (PyPI): upgrade to 5.7.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2019-10255?** Check whether you run jupyterhub (PyPI) or 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

- jupyterhub (PyPI): upgrade to 0.9.6 or later

  ```sh
  pip install "jupyterhub>=0.9.6"
  ```

- notebook (PyPI): upgrade to 5.7.8 or later

  ```sh
  pip install "notebook>=5.7.8"
  ```


## Affected products

- jupyterhub (PyPI) ECOSYSTEM:introduced=0,fixed=0.9.6
- notebook (PyPI) ECOSYSTEM:introduced=0,fixed=5.7.8

## Identifiers

- CVE-2019-10255
- GHSA-rv62-4pmj-xw6h
- PYSEC-2026-2683
- PYSEC-2026-647

## Related threats

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- [JupyterLab HTML output sanitization bypass via clipboard paste](https://junglewise.ai/threats/cve-2026-102831-jupyterlab-is-an-extensible-environment-for-interactive-and)
- [JupyterHub unauthenticated denial of service in login form handling](https://junglewise.ai/threats/cve-2026-54338-jupyterhub-unauthenticated-denial-of-service-in-login-form)
- [PYSEC-2026-2536 - HTML injection in Jupyter Notebook and JupyterLab leading to DOM Clobbering](https://junglewise.ai/threats/cve-2024-43805-html-injection-in-jupyter-notebook-and-jupyterlab-leading-to-dom)
- [PYSEC-2026-2534 - JupyterLab vulnerable to potential authentication and CSRF tokens leak](https://junglewise.ai/threats/cve-2024-22421-jupyterlab-vulnerable-to-potential-authentication-and-csrf-tokens)