Provide references for CVE-2021-21339.
Where can I find more information about CVE-2021-21339?
References are available at: https://packagist.org/packages/typo3/cms-core, https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-qx3w-4864-94ch, https://typo3.org/security/advisory/typo3-core-sa-2021-006.