CVE-2026-5422

A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the getospath() function within jupyterserver/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 rootdir to bypass the check. Additionally, the toos_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.

Database specific

{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/5xxx/CVE-2026-5422.json",
    "cna_assigner": "@huntr_ai",
    "cwe_ids": [
        "CWE-23"
    ]
}

References

Affected packages

Git / github.com/jupyter-server/jupyter_server

Affected ranges

Type

GIT

Repo

https://github.com/jupyter-server/jupyter_server

Events

Introduced

3b03c644b56cf100f4535f70e2e8f4a45a57a5b8

Last affected

3b03c644b56cf100f4535f70e2e8f4a45a57a5b8

Database specific

{
    "source": "CPE_STRING",
    "cpe": "cpe:2.3:a:jupyter:jupyter_server:2.17.0:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "2.17.0"
        },
        {
            "last_affected": "2.17.0"
        }
    ]
}

Affected versions

2.*

2.17.0

v2.*

v2.17.0

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-5422.json"