- Component Type: TYPO3 CMS
- Subcomponent: Link Handling (ext:core, ext:frontend)
- 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
It has been discovered that t3:// URL handling and typolink functionality are vulnerable to cross-site scripting. Not only regular backend forms are affected but also frontend extensions which use the rendering with typolink.
Update to TYPO3 versions 8.7.30 or 9.5.12 or 10.2.2 that fix the problem described.
Thanks to Oliver Hader who reported this issue and to TYPO3 framework mergers Susanne Moog, Oliver Hader and Frank Nägler who analyzed and fixed the issue.
All security related code changes are tagged so that you can easily look them up in our review system.