CVE-2026-39378 (GCVE-0-2026-39378)

Vulnerability from cvelistv5 – Published: 2026-04-21 00:17 – Updated: 2026-04-21 13:43
VLAI?
Title
nbconvert has an Arbitrary File Read via Path Traversal in HTMLExporter Image Embedding
Summary
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.
Severity ?
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-73 - External Control of File Name or Path
Assigner
References
Impacted products
Vendor Product Version
jupyter nbconvert Affected: >= 6.5, < 7.17.1
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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