It has been discovered backend users not having read access to specific pages still could see them in the page tree which actually should be disallowed. A valid backend user account is needed in order to exploit this vulnerability.

References

• https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms/2019-05-07-4.yaml
• https://typo3.org/security/advisory/typo3-core-sa-2019-009