JupyterGHSA-7jqv-fw35-gmx9
nbconvert has an Arbitrary File Read via Path Traversal in HTMLExporter Image Embedding
Medium6.5CVE-2026-39378 · Published Apr 21, 2026 · updated Sep 10, 2026
## Summary 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. ## Patches Upgrade to nbconvert 7.17.1 ## Workarounds Do not enable `HTMLExporter.embed_images` (it is not enabled by default).
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| nbconvert PyPI | >= 6.5.0, < 7.17.1 | 7.17.1 |
Details and references
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