cross-site inclusion (XSSI) of files in jupyter-server
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Security bypass, Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-284 and CWE-79.
Summary
jupyter-server is the backend for Jupyter web applications. Improper cross-site credential checks on `/files/` URLs could allow exposure of certain file contents, or accessing files when opening untrusted files via "Open image in new tab". This issue has been addressed in commit `87a49272728` which has been included in release `2.7.2`. Users are advised to upgrade. Users unable to upgrade may use the lower performance `--ContentsManager.files_handler_class=jupyter_server.files.handlers.FilesHandler`, which implements the correct checks.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| jupyterlab | jupyter_server | before 2.7.2 | 2.7.2 | Patch available | CNA |
| — | jupyter-server (PyPI) | before 2.7.2 | 2.7.2 | Patch available | GHSA-64x5-55rw-9974 |
- jupyter_server Vendorjupyterlab Affected before 2.7.2 Fixed in 2.7.2 Patch available CNA
- jupyter-server (PyPI) Vendor— Affected before 2.7.2 Fixed in 2.7.2 Patch available GHSA-64x5-55rw-9974
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:jupyter:jupyter_server:*:*:*:*:*:*:*:* | before 2.7.2 | Vulnerable | jupyterlab |
- cpe:2.3:a:jupyter:jupyter_server:*:*:*:*:*:*:*:* Versions before 2.7.2 Vulnerable ·jupyterlab
Remediation
- Fix · CNA jupyter_server (jupyter-server) Fixed in 2.7.2
- Fix · GHSA-64x5-55rw-9974 jupyter-server (PyPI) Fixed in 2.7.2 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2023-40170
- 2026-10-03 Alias added: GHSA-64x5-55rw-9974
- 2026-11-04 EPSS moved to the 50th–90th percentile
References
Patch 1
Advisory 2
Other 6
- https://lists.fedoraproject.org/archives/list/[email protected]/message/XDKQAWQN6SQTOVACZNXYKEHWQXGG4DOF/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/NRP7DNZYVOIA4ZB3U3ZWKTFZEPYWNGCQ/
- https://github.com/jupyter-server/jupyter_server
- https://github.com/pypa/advisory-database/tree/main/vulns/jupyter-server/PYSEC-2023-157.yaml
- https://lists.fedoraproject.org/archives/list/[email protected]/message/NRP7DNZYVOIA4ZB3U3ZWKTFZEPYWNGCQ
- https://lists.fedoraproject.org/archives/list/[email protected]/message/XDKQAWQN6SQTOVACZNXYKEHWQXGG4DOF
More jupyterlab Jupyter Server vulnerabilities
- TI-2026-05842 CORS Origin Validation Bypass in jupyter-server CVSS 3.1HIGH 8.8
- TI-2026-04748 Path Traversal in jupyter/jupyter CVSS 3.1HIGH 8.1
- TI-2026-27533 jupyter-server path traversal allows access to sibling directories sharing root_dir name prefix CVSS 4.0HIGH 7.6
- TI-2025-38102 jupyter_server next parameter open redirect can redirect users to external domains CVSS 4.0MEDIUM 6.3
- TI-2026-32614 Jupyter Server: Stored XSS in `NbconvertFileHandler` / `NbconvertPostHandler` via missing `sandbox` CSP CVSS 4.0CRITICAL 9.3
- TI-2024-23252 Jupyter server on Windows discloses Windows user password hash CVSS 3.1HIGH 7.5
Sources
- CVE-2023-40170 · CVE Program
- CVE-2023-40170 · NVD
- FIRST EPSS
- GHSA-64x5-55rw-9974 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-40170 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences