CVE-2026-39377
published 2026-04-21CVE-2026-39377: The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary…
PriorityP337medium6.5CVSS 3.1
AVNACLPRNUIRSUCNIHAN
EPSS
0.27%
18.3th percentile
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
21 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| jupyter | nbconvert | — | — |
| jupyter | nbconvert | >= 6.5.0 < 7.17.1 | 7.17.1 |
| jupyter | nbconvert | >= 6.5.0 < 7.17.1 | 7.17.1 |
| mta | mta-solution-server-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-datascience-cpu-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-minimal-cpu-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-pytorch-cuda-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-pytorch-llmcompressor-cuda-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-pytorch-rocm-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-tensorflow-cuda-py312-rhel9 | — | — |
| rhoai | odh-pipeline-runtime-tensorflow-rocm-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-datascience-cpu-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-minimal-cpu-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-minimal-cuda-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-minimal-rocm-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-pytorch-cuda-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-pytorch-llmcompressor-cuda-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-pytorch-rocm-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-tensorflow-cuda-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-tensorflow-rocm-py312-rhel9 | — | — |
| rhoai | odh-workbench-jupyter-trustyai-cpu-py312-rhel9 | — | — |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
vendor_redhat6.5MEDIUM
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Red Hat
nbconvert: nbconvert: Arbitrary file write via crafted Jupyter notebook cell attachment filenames
vendor_redhat·2026-04-21·CVSS 6.5
CVE-2026-39377 [MEDIUM] CWE-22 nbconvert: nbconvert: Arbitrary file write via crafted Jupyter notebook cell attachment filenames
nbconvert: nbconvert: Arbitrary file write via crafted Jupyter notebook cell attachment filenames
A flaw was found in nbconvert, a tool used to convert Jupyter notebooks. When processing notebooks containing specially crafted cell attachment filenames, a remote attacker can exploit a path traversal vulnerability. This allows the attacker to write arbitrary files to locations outside the intended output directory, gaining complete control over both the destination path and file extension.
Package: mta/mta-solution-server-rhel9 (Migration Toolkit for Applications 8) - Fix deferred
Package: rhoai/odh-pipeline-runtime-datascience-cpu-py312-rhel9 (Red Hat OpenShift AI (RHOAI)) - Fix deferred
Package: rhoai/odh-pipeline-runtime-minimal-cpu-py312-rhel9 (Red Hat OpenShift AI (RHOAI)) - Fix def
GHSA
nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames
ghsa·2026-04-21
CVE-2026-39377 [MEDIUM] CWE-22 nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames
nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames
# Arbitrary File Write via Path Traversal in Cell Attachment Filenames
## Summary
nbconvert allows 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.
## Impact
This vulnerability allows writing files with arbitrary content to arbitrary filesystem locations, limited only by the permissions of the process running nbconvert. The attacker controls:
- Full destination path
No detection rules found.
No public exploits indexed.
2026-04-21
Published