The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.

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History

Tue, 21 Apr 2026 02:45:00 +0000

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

Tue, 21 Apr 2026 01:15:00 +0000

Type Values Removed Values Added
Description The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.
Title nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames
Weaknesses CWE-22
CWE-73
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-04-21T00:14:59.937Z

Reserved: 2026-04-06T21:29:17.350Z

Link: CVE-2026-39377

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-21T01:16:05.937

Modified: 2026-04-21T01:16:05.937

Link: CVE-2026-39377

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-21T02:30:25Z

Weaknesses