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.
- Score
- CVSS 3.1 6.5 Medium
- Status
- Analyzed - security-advisories@github.com
- Published
- 2026-04-21
- Last modified
- 2026-10-26
- Weaknesses
- CWE-22, CWE-73
Affected products
References
- https://github.com/jupyter/nbconvert/security/advisories/GHSA-7jqv-fw35-gmx9
- https://github.com/jupyter/nbconvert/releases/tag/v7.17.1
