A vulnerability labeled as problematic has been found in Jupyter JupyterLab up to 4.5.9/4.6.1 . Affected is an unknown function of the file packages/notebook-extension/src/index.ts of the component Notebook Extension . Executing a manipulation of the argument sideBySideLeftMarginOverride/sideBySideRightMarginOverride can lead to code injection. This vulnerability appears as CVE-2026-73417 . The attack may be performed from remote. There is no available exploit. The affected component should be u