Jupyter Server Proxy allows users to run arbitrary external processes alongside their Jupyter notebook servers and provides authenticated web access. Prior to versions 3.2.3 and 4.1.1, Jupyter Server Proxy did not check user authentication appropriately when proxying websockets, allowing unauthenticated access to anyone who had network access to the Jupyter server endpoint. This vulnerability can allow unauthenticated remote access to any websocket endpoint set up to be accessible via Jupyter Server Proxy. In many cases, this leads to remote unauthenticated arbitrary code execution, due to how affected instances use websockets. The websocket endpoints exposed by `jupyter_server` itself is not affected. Projects that do not rely on websockets are also not affected. Versions 3.2.3 and 4.1.1 contain a fix for this issue.

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.

JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook and Architecture. This vulnerability depends on user interaction by opening a malicious 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 version 4.0.11 has been patched. Users are advised to upgrade. Users unable to upgrade should disable the table of contents extension.

jupyter-lsp is a coding assistance tool for JupyterLab (code navigation + hover suggestions + linters + autocompletion + rename) using Language Server Protocol. Installations of jupyter-lsp running in environments without configured file system access control (on the operating system level), and with jupyter-server instances exposed to non-trusted network are vulnerable to unauthorised access and modification of file system beyond the jupyter root directory. This issue has been patched in version 2.2.2 and all users are advised to upgrade. Users unable to upgrade should uninstall jupyter-lsp.

dockerspawner is a tool to spawn JupyterHub single user servers in Docker containers. Users of JupyterHub deployments running DockerSpawner starting with 0.11.0 without specifying `DockerSpawner.allowed_images` configuration allow users to launch _any_ pullable docker image, instead of restricting to only the single configured image, as intended. This issue has been addressed in commit `3ba4b665b` which has been included in dockerspawner release version 13. Users are advised to upgrade. Users unable to upgrade should explicitly set `DockerSpawner.allowed_images` to a non-empty list containing only the default image will result in the intended default behavior.

The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. Unhandled errors in API requests coming from an authenticated user include traceback information, which can include path information. There is no known mechanism by which to trigger these errors without authentication, so the paths revealed are not considered particularly sensitive, given that the requesting user has arbitrary execution permissions already in the same environment. A fix has been introduced in commit `0056c3aa52` which no longer includes traceback information in JSON error responses. For compatibility, the traceback field is present, but always empty. This commit has been included in version 2.11.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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.

jupyter-server is the backend for Jupyter web applications. Open Redirect Vulnerability. Maliciously crafted login links to known Jupyter Servers can cause successful login or an already logged-in session to be redirected to arbitrary sites, which should be restricted to Jupyter Server-served URLs. This issue has been addressed in commit `29036259` which is included in release 2.7.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Jupyter Core is a package for the core common functionality of Jupyter projects. Jupyter Core prior to version 4.11.2 contains an arbitrary code execution vulnerability in `jupyter_core` that stems from `jupyter_core` executing untrusted files in CWD. This vulnerability allows one user to run code as another. Version 4.11.2 contains a patch for this issue. There are no known workarounds.

The GitHub Security Lab discovered sixteen ways to exploit a cross-site scripting vulnerability in nbconvert. When using nbconvert to generate an HTML version of a user-controllable notebook, it is possible to inject arbitrary HTML which may lead to cross-site scripting (XSS) vulnerabilities if these HTML notebooks are served by a web server (eg: nbviewer).