id: PYSEC-2026-2532
published: "2026-07-13T15:46:13.935289Z"
modified: "2026-07-13T16:04:22.645443Z"
aliases:
- CVE-2026-5422
- GHSA-gf7q-q4j7-hp7c
summary: "Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() "
details: 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.
affected:
- package:
    name: jupyter-server
    ecosystem: PyPI
    purl: pkg:pypi/jupyter-server
  ranges:
  - type: ECOSYSTEM
    events:
    - introduced: "0"
    - fixed: 2.18.2
  versions:
  - 0.0.0
  - 0.0.1
  - 0.0.2
  - 0.0.3
  - 0.0.4
  - 0.0.5
  - 0.1.0
  - 0.1.1
  - 0.2.0
  - 0.2.1
  - 0.3.0
  - 1.0.0
  - 1.0.0rc0
  - 1.0.0rc1
  - 1.0.0rc10
  - 1.0.0rc11
  - 1.0.0rc12
  - 1.0.0rc13
  - 1.0.0rc14
  - 1.0.0rc15
  - 1.0.0rc16
  - 1.0.0rc2
  - 1.0.0rc3
  - 1.0.0rc4
  - 1.0.0rc5
  - 1.0.0rc6
  - 1.0.0rc7
  - 1.0.0rc8
  - 1.0.0rc9
  - 1.0.1
  - 1.0.10
  - 1.0.11
  - 1.0.2
  - 1.0.3
  - 1.0.4
  - 1.0.5
  - 1.0.6
  - 1.0.7
  - 1.0.8
  - 1.0.9
  - 1.1.0
  - 1.1.1
  - 1.1.2
  - 1.1.3
  - 1.1.4
  - 1.10.0
  - 1.10.1
  - 1.10.2
  - 1.11.0
  - 1.11.1
  - 1.11.2
  - 1.12.0
  - 1.12.1
  - 1.13.0
  - 1.13.1
  - 1.13.2
  - 1.13.3
  - 1.13.4
  - 1.13.5
  - 1.15.0
  - 1.15.1
  - 1.15.2
  - 1.15.3
  - 1.15.4
  - 1.15.5
  - 1.15.6
  - 1.16.0
  - 1.17.0
  - 1.17.1
  - 1.18.0
  - 1.18.1
  - 1.19.0
  - 1.19.1
  - 1.2.0
  - 1.2.1
  - 1.2.2
  - 1.2.3
  - 1.21.0
  - 1.23.0
  - 1.23.1
  - 1.23.2
  - 1.23.3
  - 1.23.4
  - 1.23.5
  - 1.23.6
  - 1.24.0
  - 1.3.0
  - 1.4.0
  - 1.4.1
  - 1.5.0
  - 1.5.1
  - 1.6.0
  - 1.6.1
  - 1.6.2
  - 1.6.3
  - 1.6.4
  - 1.7.0
  - 1.7.0a1
  - 1.7.0a2
  - 1.8.0
  - 1.9.0
  - 2.0.0
  - 2.0.0a0
  - 2.0.0a1
  - 2.0.0a2
  - 2.0.0b0
  - 2.0.0b1
  - 2.0.0rc0
  - 2.0.0rc1
  - 2.0.0rc2
  - 2.0.0rc3
  - 2.0.0rc4
  - 2.0.0rc5
  - 2.0.0rc6
  - 2.0.0rc7
  - 2.0.0rc8
  - 2.0.1
  - 2.0.2
  - 2.0.3
  - 2.0.4
  - 2.0.5
  - 2.0.6
  - 2.0.7
  - 2.1.0
  - 2.10.0
  - 2.10.1
  - 2.11.0
  - 2.11.1
  - 2.11.2
  - 2.12.0
  - 2.12.1
  - 2.12.2
  - 2.12.3
  - 2.12.4
  - 2.12.5
  - 2.13.0
  - 2.14.0
  - 2.14.1
  - 2.14.2
  - 2.15.0
  - 2.16.0
  - 2.17.0
  - 2.18.0
  - 2.18.1
  - 2.2.0
  - 2.2.1
  - 2.3.0
  - 2.4.0
  - 2.5.0
  - 2.6.0
  - 2.7.0
  - 2.7.1
  - 2.7.2
  - 2.7.3
  - 2.8.0
  - 2.9.0
  - 2.9.1
references:
- type: ADVISORY
  url: https://nvd.nist.gov/vuln/detail/CVE-2026-5422
- type: PACKAGE
  url: https://github.com/jupyter-server/jupyter_server
- type: WEB
  url: https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0f
- type: WEB
  url: http://github.com/jupyter-server/jupyter_server/commit/0d829f2c35a481c3b24ecbe1e25a6f79954e88f2
- type: PACKAGE
  url: https://pypi.org/project/jupyter-server
- type: ADVISORY
  url: https://github.com/advisories/GHSA-gf7q-q4j7-hp7c
severity:
- type: CVSS_V3
  score: CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N