{"id":"CVE-2026-39378","aliases":["GHSA-7jqv-fw35-gmx9","PYSEC-2026-2230"],"title":"nbconvert has an Arbitrary File Read via Path Traversal in HTMLExporter Image Embedding","summary":"nbconvert has an Arbitrary File Read via Path Traversal in HTMLExporter Image Embedding","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","vendor":"nbconvert","product":"nbconvert","ecosystem":"pip","affected":["nbconvert >= 6.5.0, < 7.17.1"],"patched":["nbconvert 7.17.1"],"published":"2026-04-21","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:43.685983757Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-7jqv-fw35-gmx9","references":[{"url":"https://github.com/jupyter/nbconvert/security/advisories/GHSA-7jqv-fw35-gmx9"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39378"},{"url":"https://github.com/jupyter/nbconvert"},{"url":"https://github.com/jupyter/nbconvert/releases/tag/v7.17.1"}],"tags":["osv","pip"],"epss":0.00306,"epssPercentile":0.23612,"ingestedAt":"2026-07-13T18:57:54.580Z","slug":"CVE-2026-39378","body":"## Overview\n\n## Summary\n\nWhen `HTMLExporter.embed_images=True`, nbconvert's markdown renderer allows arbitrary file read via path traversal in image references. A malicious notebook can exfiltrate sensitive files from the conversion host by embedding them as base64 data URIs in the output HTML.\n\n## Patches\n\nUpgrade to nbconvert 7.17.1\n\n## Workarounds\n\nDo not enable `HTMLExporter.embed_images` (it is not enabled by default).\n\n## Affected packages\n\n- `nbconvert >= 6.5.0, < 7.17.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `nbconvert 7.17.1`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}