Jupyter

Jupyter nbconvert versions up to 7.17.1 are vulnerable to an arbitrary file write attack via path traversal in malicious notebook cell metadata, allowing execution of arbitrary file writes when exporting to specific formats.

Multiple vulnerabilities in JupyterHub allow a remote, authenticated attacker to achieve privilege escalation, bypass security measures, manipulate data, and trigger a denial-of-service.

JupyterLab is vulnerable to a cross-site scripting (XSS) attack via the system clipboard that allows unauthorized JavaScript execution within the user's session when pasting cells from an external source.

Jupyter Server versions prior to 2.21.0 inadvertently expose authentication tokens in plain-text 500 error logs due to improper logging of the Referer header.

A cross-site scripting (XSS) vulnerability exists in JupyterLab's image viewer, allowing an attacker to achieve remote code execution (RCE) on the JupyterLab server if a specially crafted image file is opened in the image viewer and then opened in a new browser tab; affected versions include JupyterLab prior to 4.5.10 and versions from 4.6.0 up to, but not including, 4.6.2, with patches available in versions 4.5.10 and 4.6.2.

A critical stored Cross-Site Scripting (XSS) vulnerability, CVE-2026-44727, exists in `jupyter_server` versions up to 2.19.0 due to a missing `sandbox` directive in Content-Security-Policy (CSP) headers, allowing authenticated attackers to craft malicious notebooks that exfiltrate victim tokens and achieve kernel Remote Code Execution (RCE) when viewed.

JupyterLab versions prior to 4.5.7 do not correctly enforce the allow-list of extensions that can be installed from PyPI Extension Manager, allowing authenticated attackers to escalate privileges and potentially exfiltrate data, move laterally, and persistently compromise server infrastructure.

Jupyter Server version 2.17.0 and earlier is vulnerable to a path traversal vulnerability due to an insufficient check on the root directory, allowing an authenticated user to access, read, write, and delete content outside the server's root directory in sibling directories that share the same prefix as the root directory, potentially leading to privilege escalation in multi-tenant environments.

A stored Cross-Site Scripting (XSS) vulnerability in Jupyter Notebook versions 7.0.0 through 7.5.5 and JupyterLab versions up to 4.5.6 allows attackers to steal authentication tokens by tricking users into interacting with malicious notebook files, leading to complete account takeover via the Jupyter REST API.

Jupyter Server versions 2.17.0 and earlier are vulnerable to a CORS origin validation bypass due to improper use of `re.match()` in validating the Origin header against the `allow_origin_pat` configuration, allowing attackers to bypass CORS restrictions.