The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. From 5.4.0 until 7.17.2, ExtractOutputPreprocessor in nbconvert/preprocessors/extractoutput.py joins the attacker-controlled cell output metadata filename to output_files_dir without limiting the result to the intended directory. When a victim converts a malicious notebook with the markdown, LaTeX, reStructuredText, or AsciiDoc exporter, path traversal in the output filename can write attacker-controlled output data to arbitrary locations accessible to the victim. Running the notebook cell again replaces the malicious output metadata, but merely converting the supplied notebook does not. This issue is fixed in version 7.17.2.

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements Present

User Interaction Active

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact High

Subsequent System Availability Impact High

Attack Vector Local

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Key SSVC decision points have not yet been added.

Affected Vendors & Products

Vendors Products
Jupyter
  • Nbconvert

No data.

No data.

References
Link Providers
https://github.com/jupyter/nbconvert/commit/ce4bd99aec31d81d759fa8eeb8643179392ec66f cve-icon cve-icon cve-icon
https://github.com/jupyter/nbconvert/releases/tag/v7.17.2 cve-icon cve-icon cve-icon
https://github.com/jupyter/nbconvert/security/advisories/GHSA-pjvx-prjx-h659 cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2026-114140 cve-icon
https://www.cve.org/CVERecord?id=CVE-2026-114140 cve-icon
History

Thu, 22 Oct 2026 12:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

threat_severity

Important

Thu, 22 Oct 2026 10:45:00 +0000

Type Values Removed Values Added
First Time appeared Jupyter
Jupyter nbconvert
Vendors & Products Jupyter
Jupyter nbconvert

Wed, 21 Oct 2026 20:30:00 +0000

Type Values Removed Values Added
Description The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. From 5.4.0 until 7.17.2, ExtractOutputPreprocessor in nbconvert/preprocessors/extractoutput.py joins the attacker-controlled cell output metadata filename to output_files_dir without limiting the result to the intended directory. When a victim converts a malicious notebook with the markdown, LaTeX, reStructuredText, or AsciiDoc exporter, path traversal in the output filename can write attacker-controlled output data to arbitrary locations accessible to the victim. Running the notebook cell again replaces the malicious output metadata, but merely converting the supplied notebook does not. This issue is fixed in version 7.17.2.
Title nbconvert: File write via path traversal in cell output filenames
Weaknesses CWE-22
References
Metrics cvssV4_0

{'score': 8.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-10-21T20:19:50.116Z

Updated: 2026-10-21T20:19:50.116Z

Reserved: 2026-10-20T21:53:58.473Z

Link: CVE-2026-114140

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-21T21:17:56.520

Modified: 2026-10-22T17:29:28.470

Link: CVE-2026-114140

cve-icon Redhat

Severity : Important

Publid Date: 2026-10-21T20:19:50Z

Links: CVE-2026-114140 - Bugzilla