CVE-2026-86258
MEDIUMCVSS 5.9Description
nbviewer through 1.0.1 contains a path traversal vulnerability in LocalFileHandler.can_show() that uses string-prefix comparison instead of proper path validation. Attackers can read files from sibling directories outside the configured root by requesting paths that share the root as a textual prefix, disclosing unintended notebooks and credentials.
Timeline
Published:September 6th, 2026 1:17 PM
Last modified:September 6th, 2026 1:17 PM
CVSS Scoring
CVSS v3: 5.9 (MEDIUM)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Weaknesses (CWE)
References & Reports
Advisories, patches, and third-party reports
- https://github.com/jupyter/nbviewer
- https://github.com/jupyter/nbviewer/blob/1.0.1/nbviewer/providers/local/handlers.py#L92-L107
- https://github.com/jupyter/nbviewer/commit/aad36106f72a1ca7721310c6fccc677ce4c744a5
- https://github.com/jupyter/nbviewer/issues/1115
- https://www.vulncheck.com/advisories/nbviewer-through-1.0.1-path-traversal-via-localfilehandler
Source: NIST NVD · Data may lag official sources by up to one minute