{"id":"CVE-2026-86258","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-86258","summary":"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…","details":"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.","published":"2026-09-06T13:17:10.830","modified":"2026-09-06T13:17:10.830","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/jupyter/nbviewer/commit/aad36106f72a1ca7721310c6fccc677ce4c744a5","label":"jupyter/nbviewer@aad3610"},"references":[{"type":"WEB","url":"https://github.com/jupyter/nbviewer"},{"type":"WEB","url":"https://github.com/jupyter/nbviewer/blob/1.0.1/nbviewer/providers/local/handlers.py#L92-L107"},{"type":"WEB","url":"https://github.com/jupyter/nbviewer/commit/aad36106f72a1ca7721310c6fccc677ce4c744a5"},{"type":"WEB","url":"https://github.com/jupyter/nbviewer/issues/1115"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/nbviewer-through-1.0.1-path-traversal-via-localfilehandler"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-09-06T13:17:10.830"}}