CVE-2026-39377: nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames
jupyter · nbconvert
Affected: jupyter nbconvert · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 18% of scored CVEs
DescriptionCVE.org
The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- jupyter · nbconvert>= 6.5, < 7.17.1
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- jupyter
- Published
- April 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-39377 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.