TYPO3-CORE-SA-2020-003: Cross-Site Scripting in Link Handling

Categories: Development Created by Oliver Hader
It has been discovered that TYPO3 CMS is vulnerable to cross-site scripting.

Problem Description

It has been discovered that link tags generated by typolink functionality are vulnerable to cross-site scripting - properties being assigned as HTML attributes have not been parsed correctly.


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


Thanks to Josef Glatz who reported this issue and to TYPO3 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.