CVEvulnerability
CVE-2026-42557
8.6 HIGH
Official page ↗
- Status
- Modified
- Published
- 2026-05-13
- Last modified
- 2026-10-25
- Assigner
- [email protected]
- CVSS 4.0 ([email protected])
- 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/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 3.1 ([email protected])
- 9.6 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
- CVSS 3.1 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)
- 8.8 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-79
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.
Affected configurations
• jupyter jupyterlab (< 4.5.7)
• jupyter notebook (>= 7.0.0 < 7.5.6)
Related
Weakness · CWE (1)
- CWE-79 Improper Neutralization of Input During Web Page Generation weakness
References
- https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-mqcg-5x36-vfcg Mitigation, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:43038 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:60520 access.redhat.com
- https://access.redhat.com/security/cve/CVE-2026-42557 access.redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2477086 bugzilla.redhat.com
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42557.json security.access.redhat.com