Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-40171— Jupyter Notebook and JupyterLab token theft via stored XSS in help command linker

Quick assessment

Affected
jupyter notebook
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Jupyter Notebook是Project Jupyter开源的一套用于创建、共享代码和说明性文本文档的开源Web应用程序。JupyterLab是JupyterLab开源的一个用于交互式和可重复计算的可扩展环境，基于 Jupyter Notebook 和架构。 Jupyter多款产品存在跨站脚本漏洞，该漏洞源于帮助命令链接器存在存储型跨站脚本，可能导致攻击者通过恶意笔记本文件窃取身份验证令牌并完全接管Jupyter会话。以下产品及版本受到影响：Jupyter Notebook 7.0.0至7.5.5

AI Predicted 9.1 Difficulty: Easy EPSS 0.66% · P50

Affected Version Matrix 4

VendorProduct Version RangeStatus
jupyter notebook >=7.0.0, <= 7.5.5 affected
jupyter-notebook help-extension >=7.0.0,<= 7.5.5 affected
jupyterlab help-extension <=4.5.6 affected
jupyterlab jupyterlab <= 4.5.6 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-40171

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Jupyter Notebook and JupyterLab token theft via stored XSS in help command linker
Source: CVE Program / CVE List V5
Vulnerability Description
In Jupyter Notebook versions 7.0.0 through 7.5.5, JupyterLab versions 4.5.6 and earlier, and the corresponding @jupyter-notebook/help-extension and @jupyterlab/help-extension packages before 7.5.6 and 4.5.7, a stored cross-site scripting issue in the help command linker can be chained with attacker-controlled notebook content to steal authentication tokens with a single click. An attacker can craft a malicious notebook file containing elements that appear indistinguishable from legitimate controls and trigger execution when a user interacts with them. Successful exploitation allows theft of the user's authentication token and complete takeover of the Jupyter session through the REST API, including reading files, creating or modifying files, accessing kernels to execute arbitrary code, and creating terminals for shell access. This issue has been fixed in Notebook 7.5.6, JupyterLab 4.5.7, @jupyter-notebook/help-extension 7.5.6, and @jupyterlab/help-extension 4.5.7. As a workaround, disable the affected help extensions or set allowCommandLinker to false in the sanitizer configuration.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
在Web页面生成时对输入的转义处理不恰当(跨站脚本)
Source: CVE Program / CVE List V5
Vulnerability Title
Jupyter多款产品 跨站脚本漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Jupyter Notebook是Project Jupyter开源的一套用于创建、共享代码和说明性文本文档的开源Web应用程序。JupyterLab是JupyterLab开源的一个用于交互式和可重复计算的可扩展环境，基于 Jupyter Notebook 和架构。 Jupyter多款产品存在跨站脚本漏洞，该漏洞源于帮助命令链接器存在存储型跨站脚本，可能导致攻击者通过恶意笔记本文件窃取身份验证令牌并完全接管Jupyter会话。以下产品及版本受到影响：Jupyter Notebook 7.0.0至7.5.5
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
jupyter notebook >=7.0.0, <= 7.5.5 -
jupyterlab help-extension <=4.5.6 -
jupyterlab jupyterlab <= 4.5.6 -
jupyter-notebook help-extension >=7.0.0,<= 7.5.5 -

II. Public POCs for CVE-2026-40171

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-40171

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-40171 (1)

IV. Related Vulnerabilities

Same product: notebook
Same vendor: jupyter
Same weakness: CWE-79

V. Comments for CVE-2026-40171

No comments yet

Leave a comment