TYPO3 is a free and open source Content Management Framework. Applications that use `TYPO3\CMS\Core\Http\Uri` to parse externally provided URLs (e.g., via a query parameter) and validate the host of the parsed URL may be vulnerable to open redirect or SSRF attacks if the URL is used after passing the validation checks. Users are advised to update to TYPO3 versions 9.5.49 ELTS, 10.4.48 ELTS, 11.5.42 LTS, 12.4.25 LTS, 13.4.3 which fix the problem described. There are no known workarounds for this vulnerability.

TYPO3 Potential Open Redirect via Parsing Differences