tar filter allows writing outside destination via empty-named symlink

{
  "id": "6c1e8b80697eeb0e930854aebb5fffd321253ee41286e0c2516dfd8b4f125cd4",
  "url": "https://www.cve.org/CVERecord?id=CVE-2026-114583",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "tar filter allows writing outside destination via empty-named symlink",
    "summary": "tarfile.tar_filter could be bypassed using crafted link entries, including symlinks with empty or directory-like names, to redirect later archive members outside the intended extraction directory. This allowed a malicious tar archive to cause tarfile.extractall() with filter=\"tar\" to write files outside the destination directory, subject to the permissions of the extracting process. This is the tarfile.tar_filter counterpart of CVE-2026-7774, which covered tarfile.data_filter.",
    "evidence": "cve:CVE-2026-114583",
    "products": [
      {
        "name": {
          "value": "CPython",
          "evidence": "/containers/cna/affected/0/product"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-114583",
      "aliases": [
        "CVE-2026-114583"
      ],
      "metrics": [
        {
          "format": "CVSS",
          "cvssV4_0": {
            "Safety": "NOT_DEFINED",
            "version": "4.0",
            "Recovery": "NOT_DEFINED",
            "baseScore": 6.9,
            "Automatable": "NOT_DEFINED",
            "attackVector": "LOCAL",
            "baseSeverity": "MEDIUM",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "exploitMaturity": "NOT_DEFINED",
            "providerUrgency": "NOT_DEFINED",
            "userInteraction": "NONE",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "privilegesRequired": "NONE",
            "subIntegrityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH",
            "subAvailabilityImpact": "NONE",
            "vulnAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "affected": [
        {
          "repo": "https://github.com/python/cpython",
          "vendor": "Python Software Foundation",
          "modules": [
            "tarfile"
          ],
          "product": "CPython",
          "versions": [
            {
              "status": "affected",
              "version": "0",
              "lessThan": "3.11.18",
              "versionType": "python"
            },
            {
              "status": "affected",
              "version": "3.12.0",
              "lessThan": "3.12.16",
              "versionType": "python"
            },
            {
              "status": "affected",
              "version": "3.13.0",
              "lessThan": "3.13.18",
              "versionType": "python"
            },
            {
              "status": "affected",
              "version": "3.14.0",
              "lessThan": "3.14.10",
              "versionType": "python"
            },
            {
              "status": "affected",
              "version": "3.15.0",
              "lessThan": "3.15.2",
              "versionType": "python"
            },
            {
              "status": "affected",
              "version": "3.16.0a1",
              "lessThan": "3.16.0",
              "versionType": "python"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "modified": "2026-10-27T00:36:15.766Z",
      "provider": "cve",
      "references": [
        "https://github.com/python/cpython/pull/160098",
        "https://github.com/python/cpython/issues/160097",
        "https://mail.python.org/archives/list/security-announce@python.org/thread/43JOWPRAV5DI3VZ4FUEUAZOHCATXXOCK/",
        "https://github.com/python/cpython/commit/0901ad4ffb22605f12b705d1c1197f0a01f0ba0b",
        "https://github.com/python/cpython/commit/c6ada40177436e4e2533a7b252082b5f0c043477",
        "https://github.com/python/cpython/commit/e7e0b3523ad6ba8472873dda594cf4021a16f8b5",
        "https://github.com/python/cpython/commit/04d8fca7da2cf3ebc0881fec8a53a1330c3b665d",
        "https://github.com/python/cpython/commit/bc93f8ad4c4a0f92d184ec8fccc8ff8a651dcec2",
        "https://github.com/python/cpython/commit/f4401da82e2baec5dab06cf070fbca77d53220f0"
      ],
      "provider_metadata": {
        "cna": {
          "orgId": "28c92f92-d60d-412d-b760-e73465c3df22",
          "shortName": "PSF",
          "dateUpdated": "2026-10-27T00:36:15.766Z"
        }
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-114583",
        "evidence": "/cveMetadata/cveId"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/containers/cna/metrics"
  },
  "source_id": "core-cve",
  "document_id": 372982,
  "published_at": "2026-10-22T20:57:36.019+00:00"
}