{"id":"CVE-2026-19418","summary":"TYPO3 CMS - Broken Access Control in Backend and Install Tool","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.","modified":"2026-08-15T04:25:19.556809190Z","published":"2026-08-11T07:29:37.478Z","database_specific":{"cwe_ids":["CWE-346","CWE-352"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/19xxx/CVE-2026-19418.json","cna_assigner":"TYPO3"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/typo3/typo3","events":[{"introduced":"fd8745e46bb11773e85524b8ee9650dabe340713"},{"introduced":"6d6bd23afff6a48ee3efeaa68eb829820397d6a1"},{"fixed":"8273e2eb49cef644956175c8325b64d2bf064ab7"},{"fixed":"dea0f4d4535620a43e02f2e1c0b6558a963b1b19"},{"fixed":"4a75e862c589c85d795d7c65dcdc835f8f413efc"},{"fixed":"a0e8ee06a40e959b9e7b06a4b1cb19d3a0d3dcf7"},{"fixed":"ae0abd329d52285fe6e92804c3608820ad45e872"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"13.0.0"},{"fixed":"13.4.34"},{"introduced":"14.0.0"},{"fixed":"14.3.6"}]}}],"versions":["v14.3.5","v13.4.33","v14.3.4","v13.4.32","v14.3.3","v13.4.31","v14.3.2","v13.4.30","v14.3.1","v13.4.29","v14.3.0","v13.4.28","v14.2.0","v13.4.27","v13.4.26","v14.1.0","v13.4.25","v13.4.24","v13.4.23","v13.4.22","v13.4.21","v14.0.0","v13.4.20","v13.4.19","v13.4.18","v13.4.17","v13.4.16","v13.4.15","v13.4.14","v13.4.13","v13.4.12","v13.4.11","v13.4.10","v13.4.9","v13.4.8","v13.4.7","v13.4.6","v13.4.5","v13.4.4","v13.4.3","v13.4.2","v13.4.1","v13.4.0","v13.3.0","v13.2.1","v13.2.0","v13.1.0","v13.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-19418.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","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"}]}