TYPO3-CORE-SA-2022-012: Denial of Service in Page Error Handling

Categories: Development, TYPO3 CMS Created by Oliver Hader
It has been discovered that TYPO3 CMS is susceptible to denial of service.

Problem Description

Requesting invalid or non-existing resources via HTTP triggers the page error handler, which again could retrieve content to be shown as an error message from another page. This leads to a scenario in which the application is calling itself recursively - amplifying the impact of the initial attack until the limits of the web server are exceeded.

This vulnerability is very similar, but not identical, to the one described in TYPO3-CORE-SA-2021-005 (CVE-2021-21359).

Solution

Update to TYPO3 versions 9.5.38 ELTS, 10.4.33 or 11.5.20 that fix the problem described above.

Credits

Thanks to Daniel Schönfeld who reported this issue and to TYPO3 core & security team member Benni Mack 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.