TYPO3-CORE-SA-2018-006: Cross-Site Scripting in Online Media Asset Rendering

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: Online media asset rendering
  • Release Date: December 11, 2018
  • Vulnerability Type: Cross-Site Scripting
  • Affected Versions: 7.5.0-7.6.31, 8.0.0-8.7.20 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, online media asset rendering (*.youtube and *.vimeo files) is vulnerable to cross-site scripting. A valid backend user account or write access on the server system (e.g. SFTP) 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 András Ottó who reported this issue and to TYPO3 core team members Susanne Moog and Stefan Neufeind 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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