CVE-2026-39378

The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. In versions 6.5 through 7.17.0, when `HTMLExporter.embed_images=True`, nbconvert's markdown renderer allows arbitrary file read via path traversal in image references. A malicious notebook can exfiltrate sensitive files from the conversion host by embedding them as base64 data URIs in the output HTML. nbconvert 7.17.1 contains a fix. As a workaround, do not enable `HTMLExporter.embed_images`; it is not enabled by default.

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 HIGH

Integrity Impact NONE

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-7jqv-fw35-gmx9	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-2026-39378

Mitre link : CVE-2026-39378

CVE.ORG link : CVE-2026-39378

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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