CVE-2026-39377

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/jupyter/nbconvert/releases/tag/v7.17.1	Product
https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:jupyter:nbconvert:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-04-21 01:16

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39377

Mitre link : CVE-2026-39377

CVE.ORG link : CVE-2026-39377

JSON object : View

Products Affected

jupyter

nbconvert

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CWE-73

External Control of File Name or Path

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