GHSA-m8fw-p3cr-6jqc — typo3/cms-rte-ckeditor
MEDIUMGHSA-m8fw-p3cr-6jqc is a medium-severity (CVSS 4.7) vulnerability in typo3/cms-rte-ckeditor. A fix is available for typo3/cms-rte-ckeditor — see the affected versions and patch details below.
Cross-Site Scripting in CKEditor4 WordCount Plugin
Real-World Exposure
typo3/cms-rte-ckeditor🐘typo3/cms-rte-ckeditor🐘typo3/cms-rte-ckeditorReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
CVSS:
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C(4.4)
Problem
The WordCount plugin (npm:ckeditor-wordcount-plugin) for CKEditor4 is vulnerable to cross-site scripting when switching to the source code mode. This plugin is enabled via the Full.yaml configuration present, but is not active in the default configuration.
In default scenarios, exploiting this vulnerability requires a valid backend user account. However, if custom plugins are used on the website frontend, which accept and reflect rich-text content submitted by users, no authentication is required.
Solution
Update to TYPO3 versions 9.5.42 ELTS, 10.4.39 ELTS, 11.5.30 that fix the problem described above.
Credits
Thanks to Sybille Peters who reported this issue, and to TYPO3 core & security team member Oliver Hader who fixed the issue.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | typo3/cms-rte-ckeditor | ≥ 9.5.0&&< 9.5.42 | 9.5.42composer require typo3/cms-rte-ckeditor:^9.5.42 |
| 🐘Packagist | typo3/cms-rte-ckeditor | ≥ 10.0.0&&< 10.4.39 | 10.4.39composer require typo3/cms-rte-ckeditor:^10.4.39 |
| 🐘Packagist | typo3/cms-rte-ckeditor | ≥ 11.0.0&&< 11.5.30 | 11.5.30composer require typo3/cms-rte-ckeditor:^11.5.30 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for typo3/cms-rte-ckeditor, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update typo3/cms-rte-ckeditor to 9.5.42 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m8fw-p3cr-6jqc is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-m8fw-p3cr-6jqc can be triaged on real exposure rather than presence alone.
Tailored to GHSA-m8fw-p3cr-6jqc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-m8fw-p3cr-6jqc in your dependencies?
O3 Security finds GHSA-m8fw-p3cr-6jqc across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.