TYPO3-CORE-SA-2022-016: Sensitive Information Disclosure via YAML Placeholder Expressions in Site Configuration

Categories: Development, TYPO3 CMS Created by Oliver Hader
It has been discovered that TYPO3 CMS is susceptible to sensitive information disclosure.

Problem Description

Due to the lack of handling user-submitted YAML placeholder expressions in the site configuration backend module, attackers could expose sensitive internal information, such as system configuration or HTTP request messages of other website visitors.

A valid backend user account having administrator privileges is needed to exploit this vulnerability.


Update to TYPO3 versions 9.5.38 ELTS, 10.4.33, 11.5.20, 12.1.1 that fix the problem described above.


Thanks to TYPO3 core & security team member Oliver Hader who reported and 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

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