CVE-2026-39378

unknown
Published 2026-04-21 ยท Modified 2026-04-30
CVSS v3
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CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CVSS v4 NEW
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not yet in upstream
VIR risk
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Description

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.

Predictions

Exploit likelihood
30%
Patch ETA
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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

OSVersionStatusFixed in
debian debianbookwormaffected
debian debianbullseyeaffected
debian debianforkyfixed7.17.1-1
debian debiansidfixed7.17.1-1
debian debiantrixieaffected

Package impact

EcosystemPackageVulnerableFixed
python PyPInbconvert>=6.5.0,<7.17.17.17.1

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.