TYPO3-CORE-SA-2020-002: Cross-Site Scripting in Form Engine

Problem Description

It has been discovered that HTML placeholder attributes containing data of other database records are vulnerable to cross-site scripting. A valid backend user account is needed to exploit this vulnerability.


Update to TYPO3 versions 9.5.17 or 10.4.2 that fix the problem described.


Thanks to Florian Weiss who reported this issue and to TYPO3 active contributor Markus Klein 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

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