What is GHSA-M8FW-P3CR-6JQC?

GHSA-M8FW-P3CR-6JQC is a medium-severity cross-site scripting (XSS) vulnerability in typo3/cms-rte-ckeditor (composer), affecting versions >= 9.5.0, < 9.5.42. It is fixed in 9.5.42, 10.4.39, 11.5.30. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.

How severe is GHSA-M8FW-P3CR-6JQC?

GHSA-M8FW-P3CR-6JQC has a CVSS score of 4.7 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of typo3/cms-rte-ckeditor are affected by GHSA-M8FW-P3CR-6JQC?

typo3/cms-rte-ckeditor (composer) versions >= 9.5.0, < 9.5.42 is affected.

Is there a fix for GHSA-M8FW-P3CR-6JQC?

Yes. GHSA-M8FW-P3CR-6JQC is fixed in 9.5.42, 10.4.39, 11.5.30. Upgrade to this version or later.

Is GHSA-M8FW-P3CR-6JQC exploitable, and should I be worried?

Whether GHSA-M8FW-P3CR-6JQC is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

What actually determines whether GHSA-M8FW-P3CR-6JQC is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

How do I fix GHSA-M8FW-P3CR-6JQC?

Upgrade: typo3/cms-rte-ckeditor to 9.5.42 or later, typo3/cms-rte-ckeditor to 10.4.39 or later, typo3/cms-rte-ckeditor to 11.5.30 or later.

GHSA-M8FW-P3CR-6JQC in typo3/cms-rte-ckeditor

Q: How severe is GHSA-M8FW-P3CR-6JQC?

GHSA-M8FW-P3CR-6JQC has a CVSS score of 4.7 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Q: Which versions of typo3/cms-rte-ckeditor are affected by GHSA-M8FW-P3CR-6JQC?

typo3/cms-rte-ckeditor (composer) versions >= 9.5.0, < 9.5.42 is affected.

Q: Is there a fix for GHSA-M8FW-P3CR-6JQC?

Yes. GHSA-M8FW-P3CR-6JQC is fixed in 9.5.42, 10.4.39, 11.5.30. Upgrade to this version or later.

Q: Is GHSA-M8FW-P3CR-6JQC exploitable, and should I be worried?

Whether GHSA-M8FW-P3CR-6JQC is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk.

Q: What actually determines whether GHSA-M8FW-P3CR-6JQC is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

Q: How do I fix GHSA-M8FW-P3CR-6JQC?

Upgrade: typo3/cms-rte-ckeditor to 9.5.42 or later, typo3/cms-rte-ckeditor to 10.4.39 or later, typo3/cms-rte-ckeditor to 11.5.30 or later.

Summary

Cross-Site Scripting in CKEditor4 WordCount Plugin

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.

Credits

Thanks to Sybille Peters who reported this issue, and to TYPO3 core & security team member Oliver Hader who fixed the issue.

References

Impact

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

GHSA-M8FW-P3CR-6JQC has a CVSS score of 4.7 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (9.5.42, 10.4.39, 11.5.30); upgrading removes the vulnerable code path.

Affected versions

typo3/cms-rte-ckeditor (>= 9.5.0, < 9.5.42) typo3/cms-rte-ckeditor (>= 10.0.0, < 10.4.39) typo3/cms-rte-ckeditor (>= 11.0.0, < 11.5.30)

Security releases

typo3/cms-rte-ckeditor → 9.5.42 (composer) typo3/cms-rte-ckeditor → 10.4.39 (composer) typo3/cms-rte-ckeditor → 11.5.30 (composer)

Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.

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Remediation advice

Update to TYPO3 versions 9.5.42 ELTS, 10.4.39 ELTS, 11.5.30 that fix the problem described above.

Frequently Asked Questions

What is GHSA-M8FW-P3CR-6JQC? GHSA-M8FW-P3CR-6JQC is a medium-severity cross-site scripting (XSS) vulnerability in typo3/cms-rte-ckeditor (composer), affecting versions >= 9.5.0, < 9.5.42. It is fixed in 9.5.42, 10.4.39, 11.5.30. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
How severe is GHSA-M8FW-P3CR-6JQC? GHSA-M8FW-P3CR-6JQC has a CVSS score of 4.7 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
Which versions of typo3/cms-rte-ckeditor are affected by GHSA-M8FW-P3CR-6JQC? typo3/cms-rte-ckeditor (composer) versions >= 9.5.0, < 9.5.42 is affected.
Is there a fix for GHSA-M8FW-P3CR-6JQC? Yes. GHSA-M8FW-P3CR-6JQC is fixed in 9.5.42, 10.4.39, 11.5.30. Upgrade to this version or later.
Is GHSA-M8FW-P3CR-6JQC exploitable, and should I be worried? Whether GHSA-M8FW-P3CR-6JQC is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
What actually determines whether GHSA-M8FW-P3CR-6JQC is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
How do I fix GHSA-M8FW-P3CR-6JQC?
- Upgrade typo3/cms-rte-ckeditor to 9.5.42 or later
- Upgrade typo3/cms-rte-ckeditor to 10.4.39 or later
- Upgrade typo3/cms-rte-ckeditor to 11.5.30 or later