TYPO3-CORE-SA-2019-021: Cross-Site Scripting in Form Framework validation handling

Categories: Development Created by Frank Nägler
It has been discovered that TYPO3 CMS is vulnerable to cross-site scripting.
  • Component Type: TYPO3 CMS
  • Subcomponent: Form Framework (ext:form)
  • Release Date: December 17, 2019
  • Vulnerability Type: Cross-Site Scripting
  • Affected Versions: 8.0.0-8.7.29 and 9.0.0-9.5.11 and 10.0.0-10.2.0
  • Severity: Medium
  • Suggested CVSS v3.1: AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C
  • CVE: not assigned yet

Problem Description

It has been discovered that the output of field validation errors in the Form Framework is vulnerable to cross-site scripting.


Update to TYPO3 versions 8.7.30 or 9.5.12 or 10.2.2 that fix the problem described.


Thanks to Aslam Idrisov and an anonymous contributor who reported this issue and to TYPO3 framework merger Frank Nägler 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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