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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 13:43 UTC
CWE
  • CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-73 - External Control of File Name or Path
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8035 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
jupyter nbconvert Affected: >= 6.5, < 7.17.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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