BIT-jupyterlab-2026-42557: jupyterlab: Command linker attributes in HTML enable one-click command execution from untrusted content
JupyterLab versions prior to 4.5.7 contain a vulnerability where HTML sanitizer allowlists certain command linker attributes on button elements. This allows a notebook with a pre-saved HTML cell output containing a deceptive button to trigger arbitrary JupyterLab commands, including arbitrary code execution, on a single user click without explicit code submission. The issue is fixed in version 4.5.7.
AI Analysis
Technical Summary
JupyterLab's HTML sanitizer prior to version 4.5.7 permits data-commandlinker-command and data-commandlinker-args attributes on button elements. The CommandLinker component listens for all click events on the document body and executes the named command without verifying if the element originated from trusted JupyterLab UI. This flaw enables an attacker to embed a deceptive button in notebook HTML output that, when clicked by a user, can execute arbitrary JupyterLab commands, potentially leading to arbitrary code execution. The vulnerability is resolved in JupyterLab 4.5.7.
Potential Impact
An attacker can craft a notebook with malicious HTML output containing a button that executes arbitrary commands in JupyterLab when clicked by a user. This can lead to arbitrary code execution without the user explicitly submitting code for execution, posing a high security risk to users running vulnerable versions.
Mitigation Recommendations
This vulnerability is fixed in JupyterLab version 4.5.7. Users should upgrade to version 4.5.7 or later to remediate this issue. No additional mitigations are indicated by the vendor advisory.
BIT-jupyterlab-2026-42557: jupyterlab: Command linker attributes in HTML enable one-click command execution from untrusted content
Description
JupyterLab versions prior to 4.5.7 contain a vulnerability where HTML sanitizer allowlists certain command linker attributes on button elements. This allows a notebook with a pre-saved HTML cell output containing a deceptive button to trigger arbitrary JupyterLab commands, including arbitrary code execution, on a single user click without explicit code submission. The issue is fixed in version 4.5.7.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
JupyterLab's HTML sanitizer prior to version 4.5.7 permits data-commandlinker-command and data-commandlinker-args attributes on button elements. The CommandLinker component listens for all click events on the document body and executes the named command without verifying if the element originated from trusted JupyterLab UI. This flaw enables an attacker to embed a deceptive button in notebook HTML output that, when clicked by a user, can execute arbitrary JupyterLab commands, potentially leading to arbitrary code execution. The vulnerability is resolved in JupyterLab 4.5.7.
Potential Impact
An attacker can craft a notebook with malicious HTML output containing a button that executes arbitrary commands in JupyterLab when clicked by a user. This can lead to arbitrary code execution without the user explicitly submitting code for execution, posing a high security risk to users running vulnerable versions.
Mitigation Recommendations
This vulnerability is fixed in JupyterLab version 4.5.7. Users should upgrade to version 4.5.7 or later to remediate this issue. No additional mitigations are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BIT-jupyterlab-2026-42557
- Osv Schema Version
- 1.6.2
- Aliases
- ["CVE-2026-42557"]
- Ecosystems
- ["Bitnami"]
- Database Specific Severity
- High
- Cvss Version
- null
Threat ID: 6a4c347627e9c79719603fe0
Added to database: 07/06/2026, 23:04:22 UTC
Last enriched: 07/06/2026, 23:06:57 UTC
Last updated: 07/06/2026, 23:08:36 UTC
Views: 2
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