{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "nbconvert",
          "vendor": "jupyter",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 6.5, \u003c 7.17.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The `ExtractAttachmentsPreprocessor` passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-73",
              "description": "CWE-73: External Control of File Name or Path",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-21T00:14:59.937Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/jupyter/nbconvert/security/advisories/GHSA-4c99-qj7h-p3vg"
        },
        {
          "name": "https://github.com/jupyter/nbconvert/releases/tag/v7.17.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/jupyter/nbconvert/releases/tag/v7.17.1"
        }
      ],
      "source": {
        "advisory": "GHSA-4c99-qj7h-p3vg",
        "discovery": "UNKNOWN"
      },
      "title": "nbconvert has an Arbitrary File Write via Path Traversal in Cell Attachment Filenames"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-39377",
    "datePublished": "2026-04-21T00:14:59.937Z",
    "dateReserved": "2026-04-06T21:29:17.350Z",
    "dateUpdated": "2026-04-21T00:14:59.937Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}