jupyterlab: Command linker attributes in HTML enable one-click command execution from untrusted content
Summary
| CVE | CVE-2026-42557 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-13 16:16:48 UTC |
| Updated | 2026-08-28 16:18:01 UTC |
| Description | jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. Prior to 4.5.7, JupyterLab's HTML sanitizer allowlists data-commandlinker-command and data-commandlinker-args on button elements, while CommandLinker listens for all click events on document.body and executes the named command without checking whether the element came from trusted JupyterLab UI. A notebook with a pre-saved HTML cell output containing a deceptive button can trigger arbitrary JupyterLab commands - including arbitrary code execution - on a single user click, without any code being submitted for execution by the user. This vulnerability is fixed in 4.5.7. |
Risk And Classification
Primary CVSS: v4.0 8.6 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.003710000 probability, percentile 0.300190000 (date 2026-08-30)
Problem Types: CWE-79 | CWE-79 CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') | CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 8.6 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | DECLARED | 8.6 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| 3.1 | [email protected] | Primary | 9.6 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
| 3.1 | ADP | CVSS | 8.8 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 8.8 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
ActiveConfidentiality
HighIntegrity
HighAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
RequiredScope
ChangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Jupyter | Jupyterlab | All | All | All | All |
| Application | Jupyter | Notebook | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Jupyterlab | Jupyterlab | affected < 4.5.7 | Not specified |
| CNA | Jupyter | Notebook | affected >= 7.0.0, < 7.5.6 | Not specified |
| ADP | Red Hat | Red Hat Migration Toolkit For Applications 8.2 | unaffected 1784109883 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787076778 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787077779 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787076481 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787074331 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073913 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787074078 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073929 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073605 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073546 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073717 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073713 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI 3.4 | unaffected 1787073593 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift AI RHOAI | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:43038 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-42557 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| github.com/jupyterlab/jupyterlab/security/advisories/GHSA-mqcg-5x36-vfcg | [email protected] | github.com | Mitigation, Vendor Advisory |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42557.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:60520 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-05-13T16:02:57.063Z | Reported to Red Hat. |
| ADP | 2026-05-13T15:06:14.222Z | Made public. |
Solutions
ADP: RHSA-2026:43038: Red Hat Migration Toolkit for Applications 8.2
ADP: RHSA-2026:60520: Red Hat OpenShift AI 3.4
Workarounds
ADP: Users should avoid opening or interacting with JupyterLab notebooks from untrusted sources. Exercise caution and verify the origin of any notebook before clicking buttons within its output, as this action could lead to the execution of arbitrary commands.
There are currently no legacy QID mappings associated with this CVE.