Package Instance

HTML injection in Jupyter Notebook and JupyterLab leading to DOM Clobbering
The vulnerability depends on user interaction by opening a malicious notebook with Markdown cells, or Markdown file using JupyterLab preview feature.

A malicious user can access any data that the attacked user has access to as well as perform arbitrary requests acting as the attacked user.

JupyterLab LaTeX typesetter links did not enforce `noopener` attribute
Links generated with LaTeX typesetters in Markdown files and Markdown cells in JupyterLab and Jupyter Notebook did not include the `noopener` attribute.

This is deemed to have no impact on the default installations. Theoretically users of third-party LaTeX-rendering extensions could find themselves vulnerable to reverse tabnabbing attacks if:
- links generated by those extensions included `target=_blank` (no such extensions are known at time of writing) and
- they were to click on a link generated in LaTeX (typically visibly different from other links).

For consistency with handling on other links, new versions of JupyterLab will enforce `noopener` and `target=_blank` on all links generated by typesetters. The former will harden the resilience of JupyterLab to extensions with lack of secure defaults in link rendering, and the latter will improve user experience by preventing accidental state loss when clicking on links rendered by LaTeX typesetters.

Relative Path Traversal
JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook and Architecture. Users of JupyterLab who click on a malicious link may get their `Authorization` and `XSRFToken` tokens exposed to a third party when running an older `jupyter-server` version. JupyterLab versions 4.1.0b2, 4.0.11, and 3.6.7 are patched. No workaround has been identified, however users should ensure to upgrade `jupyter-server` to version 2.7.2 or newer which includes a redirect vulnerability fix.