It has been discovered that TYPO3 CMS is vulnerable to cross-site scripting.

Problem Description

It has been discovered that the FileDumpController (backend and frontend context) is vulnerable to cross-site scripting when malicious files are displayed using this component. A valid backend user account is needed to exploit this vulnerability.

Solution

Update to TYPO3 version 7.6.58 ELTS, 8.7.48 ELTS, 9.5.37 ELTS, 10.4.32 or 11.5.16 that fix the problem described above.

Credits

Thanks to Vautia who reported this issue and to TYPO3 core & security team member Oliver Hader who fixed the issue.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.

General Note

All security related code changes are tagged so that you can easily look them up in our review system.