{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "13.0.0"
              },
              {
                "fixed": "13.4.34"
              },
              {
                "introduced": "14.0.0"
              },
              {
                "fixed": "14.3.6"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "fd8745e46bb11773e85524b8ee9650dabe340713"
            },
            {
              "introduced": "6d6bd23afff6a48ee3efeaa68eb829820397d6a1"
            },
            {
              "fixed": "8273e2eb49cef644956175c8325b64d2bf064ab7"
            },
            {
              "fixed": "dea0f4d4535620a43e02f2e1c0b6558a963b1b19"
            },
            {
              "fixed": "4a75e862c589c85d795d7c65dcdc835f8f413efc"
            },
            {
              "fixed": "a0e8ee06a40e959b9e7b06a4b1cb19d3a0d3dcf7"
            },
            {
              "fixed": "ae0abd329d52285fe6e92804c3608820ad45e872"
            }
          ],
          "repo": "https://github.com/typo3/typo3",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "TYPO3",
    "cwe_ids": [
      "CWE-346",
      "CWE-352"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19418.json"
  },
  "details": "The referrer enforcement introduced with TYPO3-CORE-SA-2020-006 (CVE-2020-11069) became ineffective in TYPO3 v13.0, where TYPO3 CMS started serving the backend and Install Tool applications from the site's main entry script instead of the dedicated typo3/ directory.\n\nWhether a request originated from the backend or Install Tool itself was determined by comparing the referrer against the directory of the entry script, which since then is the site root. As a consequence, requests originating from any script running on one of the TYPO3 instance's own domains, such as a frontend page, were accepted by backend routes and Install Tool endpoints.\n\nAttackers able to execute JavaScript on one of those domains, for instance by exploiting a cross-site scripting vulnerability, could invoke these endpoints via Fetch/XHR with the privileges of an authenticated victim's user session. This issue affects TYPO3 CMS versions 13.0.0-13.4.33 and 14.0.0-14.3.5.",
  "id": "CVE-2026-19418",
  "modified": "2026-08-15T04:07:17.848079119Z",
  "published": "2026-08-11T07:29:37.478Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://packagist.org"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19418.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19418"
    },
    {
      "type": "ADVISORY",
      "url": "https://typo3.org/security/advisory/typo3-core-sa-2020-006"
    },
    {
      "type": "ADVISORY",
      "url": "https://typo3.org/security/advisory/typo3-core-sa-2026-021"
    },
    {
      "type": "FIX",
      "url": "https://github.com/TYPO3/typo3/commit/4a75e862c589c85d795d7c65dcdc835f8f413efc"
    },
    {
      "type": "FIX",
      "url": "https://github.com/TYPO3/typo3/commit/a0e8ee06a40e959b9e7b06a4b1cb19d3a0d3dcf7"
    },
    {
      "type": "FIX",
      "url": "https://github.com/TYPO3/typo3/commit/ae0abd329d52285fe6e92804c3608820ad45e872"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/TYPO3/typo3"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "TYPO3 CMS - Broken Access Control in Backend and Install Tool"
}