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 3.1
- 6.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N - EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 23% of CVEs (scores of 2026-10-26)
- CWEs
- CWE-22, CWE-73
- Published
- Modified
- Record from
- the NVD, synced
Affected
- jupyter:nbconvert
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-7jqv-fw35-gmx9 | PyPI | nbconvert | >=6.5.0 <7.17.1 | 7.17.1 |
| PYSEC-2026-2230 | PyPI | nbconvert | >=6.5.0 <7.17.1 | 7.17.1 |