{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-66881",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-66881",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-08-05T19:43:48.812Z",
    "updatedAt": "2026-08-06T13:03:45.814Z",
    "importedAt": "2026-10-24T01:58:25.636Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Path traversal in imported file_entries name allows arbitrary file write via URL-type entry download",
      "summary": "Relative Path Traversal vulnerability in livebook-dev livebook allows an attacker-authored notebook to write a file with attacker-controlled content to an arbitrary path.\n\nA .livemd notebook can declare file_entries metadata, each entry carrying a name. Every path that creates a file entry through the user interface validates that name with Livebook.Notebook.validate_file_entry_name/2, which requires a flat filename of alphanumerics, dashes, underscores and dots, ending in an extension. The import path does not: Livebook.LiveMarkdown.Import.file_entry_metadata_to_attrs/1 in lib/livebook/live_markdown/import.ex takes the name verbatim from the notebook source.\n\nFor a URL-type file entry, Livebook.Session.file_entry_cache_file/2 in lib/livebook/session.ex resolves that name beneath the session's temporary directory without checking that the result stays inside it, and Livebook.FileSystem.Utils.resolve_unix_like_path/2 collapses parent-directory segments while clamping only at the filesystem root. When the entry's content is requested and no cached copy exists, Livebook fetches the entry's URL and writes the response body to the resolved path, creating parent directories as needed. The attacker therefore controls both the destination and the contents of the written file, which may land anywhere the Livebook process can write. The same missing containment check is present in Livebook.Session.to_attachment_file_entry/2.\n\nA victim who opens an attacker-supplied notebook and causes the entry to be fetched triggers the write within their own authenticated session; the attacker needs no account on the target instance. URL-type entries are also not placed under notebook stamping quarantine on import, so no warning is shown.\n\nThis issue affects livebook: from 0.11.0 before 0.18.7 and from 0.19.0 before 0.19.9.",
      "affected": [
        {
          "vendor": "livebook-dev",
          "product": "livebook",
          "packageName": "livebook",
          "collectionURL": "https://repo.hex.pm",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0.11.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "0.18.7"
            },
            {
              "version": "0.19.0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "0.19.9"
            }
          ]
        },
        {
          "vendor": "livebook-dev",
          "product": "livebook",
          "packageName": "livebook-dev/livebook",
          "collectionURL": "https://ghcr.io",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "0.11.0",
              "status": "affected",
              "versionType": "other",
              "lessThan": "0.18.7"
            },
            {
              "version": "0.19.0",
              "status": "affected",
              "versionType": "other",
              "lessThan": "0.19.9"
            },
            {
              "version": "0.11.0-cuda12",
              "status": "affected",
              "versionType": "other",
              "lessThan": "0.18.7-cuda12"
            },
            {
              "version": "0.19.0-cuda12",
              "status": "affected",
              "versionType": "other",
              "lessThan": "0.19.9-cuda12"
            }
          ]
        },
        {
          "vendor": "livebook-dev",
          "product": "livebook",
          "packageName": "livebook-dev/livebook",
          "collectionURL": "https://github.com",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "c02eb984f80a543c7a52b1d882c76f56aa5be743",
              "status": "affected",
              "versionType": "git",
              "lessThan": "*",
              "changes": [
                {
                  "at": "1443dd23df6e7b9203b6797f0695a807aeb81dde",
                  "status": "unaffected"
                },
                {
                  "at": "acf4cb8c0c79b89c795b180f061be7de2d8b5aa9",
                  "status": "unaffected"
                },
                {
                  "at": "50f86982ebf36c22abeb379b55ec0f2859c83bb9",
                  "status": "unaffected"
                }
              ]
            }
          ]
        }
      ]
    }
  }
}