CVSS 4.0
8.2 highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NCVE-2026-86258
High (8.2). EPSS 0.5% chance of exploitation in the next 30 days.
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.
Severity
CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 44% of CVEs (scores of 2026-11-01)
- CWE
- CWE-22
- Published
- Modified
- Record from
- the NVD, synced
References
- 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