CVE-2026-5422
highpriority · track · 34EPSS 0.049 · 92 %ileEUUSEPSS · scored 2026-10-27
A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a trailing path separator, allowing sibling directories with names starting with the same prefix as root_dir to bypass the check. Additionally, the to_os_path() function in utils.py does not strip ".." from path parts, enabling traversal sequences to bypass the vulnerable check. This vulnerability can lead to unauthorized read/write access to files in sibling directories, potentially exposing sensitive data in shared hosting environments.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–8.1
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-gf7q-q4j7-hp7cDuplicate Advisory: Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() 2026-06-02ghsa · osvUS
### Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-5789-5fc7-67v3. This link is maintained to preserve external references. ### Original Description A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a trailing path separator, allowing sibling directories with names starting with the same prefix as root_dir to bypass the check. Additionally, the to_os_path() function in utils.py does not strip ".." from path parts, enabling traversal sequences to bypass the vulnerable check. This vulnerability can lead to unauthorized read/write access to files in sibling directories, potentially exposing sensitive data in shared hosting environments.
- PYSEC-2026-2532Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() 2026-07-13vendor · osvUS
A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a trailing path separator, allowing sibling directories with names starting with the same prefix as root_dir to bypass the check. Additionally, the to_os_path() function in utils.py does not strip ".." from path parts, enabling traversal sequences to bypass the vulnerable check. This vulnerability can lead to unauthorized read/write access to files in sibling directories, potentially exposing sensitive data in shared hosting environments.
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://github.com/jupyter-server/jupyter_server/releasesPatchcnnvd
- https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0fcnnvd
- https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0fenisa_euvd
- https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0fExploitThird Party Advisorynvd
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