{"cve":"CVE-2026-5422","nvd":{"published":"2026-06-02T10:16:25.800","modified":"2026-07-22T19:10:00.120","status":"Analyzed","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","score":8.1},"cwes":["CWE-23"],"references":["https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0f","https://huntr.com/bounties/24a36953-6490-466f-8cb2-a90d1ca56e0f"],"products":["jupyter:jupyter_server"],"source":"nvd","synced_at":"2026-10-19T22:37:48.043517290+00:00"},"epss":{"cve":"CVE-2026-5422","score":0.04858,"percentile":0.92035,"date":"2026-10-31"},"kev":null,"osv":[{"id":"PYSEC-2026-2532","url":"https://osv.dev/vulnerability/PYSEC-2026-2532","summary":"Jupyter Server vulnerable to Path Traversal via incorrect root directory boundary check in _get_os_path() ","modified":"2026-07-13T16:31:58.966038327Z","packages":[{"ecosystem":"PyPI","name":"jupyter-server","purl":"pkg:pypi/jupyter-server","ranges":["<2.18.2"],"fixed":["2.18.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}