TYPO3-CORE-SA-2018-007: Cross-Site Scripting in Backend Modal Component

Categories: Development Created by Oliver Hader
It has been discovered, that TYPO3 CMS is vulnerable to cross-site scripting.
  • Component Type: TYPO3 CMS
  • Vulnerable subcomponent: Backend modal component
  • Release Date: December 11, 2018
  • Vulnerability Type: Cross-Site Scripting
  • Affected Versions: 7.1.0-7.6.31, 8.5.0-8.7.20 and 9.0.0-9.5.1
  • Severity: Medium
  • Suggested CVSS v3.0: AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C
  • CVE: not assigned yet

Problem Description

Failing to properly encode user input, notifications shown in modal windows in the TYPO3 backend are vulnerable to cross-site scripting. A valid backend user account is needed in order to exploit this vulnerability.


Update to TYPO3 versions 7.6.32, 8.7.21 or 9.5.2 that fix the problem described.


Thanks to Joshua Westerheide who reported this issue and to TYPO3 core team member 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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