CVE-2026-40171
HighCVSS 8.4Exploitation Probability (EPSS)
Low risk41th percentile - higher than 41% of all known CVEs
Summary
In Jupyter Notebook versions 7.0.0 through 7.5.5, JupyterLab 4.5.6 and earlier, and the corresponding help-extension packages, a stored XSS in the help command linker can be chained with attacker-controlled notebook content to steal authentication tokens with a single click. Successful exploitation allows complete takeover of the Jupyter session, including file access, code execution, and terminal access.
Risk Assessment
An attacker can steal a user's authentication token and take over their Jupyter session, leading to unauthorized data access and code execution.
Recommendation
Upgrade Jupyter Notebook to 7.5.6, JupyterLab to 4.5.7, and the help-extension packages to the corresponding versions. As a workaround, disable the affected help extensions or set allowCommandLinker to false.
Related vulnerabilities
- CVE-2026-113364Critical
Buffer overflow in the data receiving process in NEC WebSAM WinShare versions 7.5.0 and earlier, 7.6.0, and 7.7.0 through 7.7.2 on Windows allows a remote unauthenticated attacker to execute arbitrary code with SYSTEM privileges via a crafted packet with a malformed data size value in the protocol header.
- CVE-2026-113363Critical
Improper input validation in the network communication processing in NEC WebSAM WinShare versions 7.2.0 through 7.5.0, 7.6.0, and 7.7.0 through 7.7.2 on Windows allows a remote unauthenticated attacker to execute arbitrary commands with SYSTEM privileges via a crafted network packet sent to the computer running WinShare.
- CVE-2026-124560Critical
A vulnerability was found in D-Link DIR-878 version 1.20B05 in the GetCAPTCHAsetting function of bin/prog.cgi (HNAP Handler component). Manipulating the uid argument results in a heap-based buffer overflow. The attack can be initiated remotely and the exploit has been made public.
- CVE-2026-119506Critical
The Frontend Admin by DynamiApps plugin (acf-frontend-form-element) through version 3.30.1 contains an incorrect privilege assignment vulnerability. The flaw allows an attacker to escalate privileges within the WordPress site.
- CVE-2026-6715Critical
IBM Concert 1.0 through 3.0.1.1 allows an attacker to supply crafted input that is incorporated into an operating system command without adequate validation or sanitization. Successful exploitation allows remote attackers to execute arbitrary commands on the underlying operating system with the privileges of the affected service.
- CVE-2026-17466Critical
IBM Optim versions 1.0.0, 1.1.0, and 1.2.0 are vulnerable to path traversal, allowing a remote authenticated attacker to obtain sensitive information.
- CVE-2026-15266Critical
IBM Concert 1.0 through 3.0.1.1 contains components that allow potentially unsafe command execution, which could be exploited to run arbitrary system commands on the host.
- CVE-2026-114464Critical
IBM Process Mining 2.0.0 through 2.2.1 has improper access control, which could allow a remote attacker to obtain sensitive information.
- CVE-2026-107331Critical
IBM DataStage on Cloud Pak for Data 5.4.0.0 has an absolute-path traversal vulnerability that could allow a remote authenticated attacker to obtain sensitive information.
- CVE-2026-109900Critical
The Melapress Role Editor plugin for WordPress (through version 1.3.0) contains an incorrect privilege assignment vulnerability that allows privilege escalation. A low-privileged user can gain a higher level of access within the system.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS