GHSA-m8fw-p3cr-6jqc
MEDIUMCross-Site Scripting in CKEditor4 WordCount Plugin
Blast Radius
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 | 9.5.42 |
| 🐘Packagist | typo3/cms-rte-ckeditor | ≥ 10.0.0&&< 10.4.39 | 10.4.39 |
| 🐘Packagist | typo3/cms-rte-ckeditor | ≥ 11.0.0&&< 11.5.30 | 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. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
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 pinpoints whether GHSA-m8fw-p3cr-6jqc is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
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 detects GHSA-m8fw-p3cr-6jqc across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.