Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Informational severity, published 16 September 2026.

Which products and versions are affected?

CKSource CKEditor 5 affected version range not specified in advisory; Drupal 10.5.0–10.6.16, 11.0.0–11.3.16, 11.4.0–11.4.6; drupal/core (Packagist) ECOSYSTEM:introduced=10.5.0,fixed=10.6.17|ECOSYSTEM:introduced=11.0.0,fixed=11.3.17|ECOSYSTEM:introduced=11.4.0,fixed=11.4.7.

Is there a fix for This vulnerability?

Yes. drupal/core (Packagist): upgrade to 10.6.17 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a web application.

Check whether you run CKSource CKEditor 5, Drupal or drupal/core (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Drupal cross-site scripting in CKEditor WYSIWYG

Severity: info · Published 2026-09-16

Drupal is a web content management system widely used to power websites. The WYSIWYG editor in Drupal integrates CKEditor, a third-party library for rich text editing. An authenticated attacker who can create or edit content could inject malicious JavaScript to compromise site administrators and other privileged users who interact with the editor. This could lead to account takeover, malware distribution, or sensitive data theft.

Technologies: Drupal, drupal/core (Packagist). Vendors: CKSource, Drupal, Packagist.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Informational severity, published 16 September 2026.
Which products and versions are affected?: CKSource CKEditor 5 affected version range not specified in advisory; Drupal 10.5.0–10.6.16, 11.0.0–11.3.16, 11.4.0–11.4.6; drupal/core (Packagist) ECOSYSTEM:introduced=10.5.0,fixed=10.6.17|ECOSYSTEM:introduced=11.0.0,fixed=11.3.17|ECOSYSTEM:introduced=11.4.0,fixed=11.4.7.
Is there a fix for This vulnerability?: Yes. drupal/core (Packagist): upgrade to 10.6.17 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network, in a web application.
Am I affected?: Check whether you run CKSource CKEditor 5, Drupal or drupal/core (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

drupal/core (Packagist): upgrade to 10.6.17 or later
```
composer require drupal/core:^10.6.17
```

Technical details

CKEditor 5 contains a stored cross-site scripting (XSS) vulnerability in its engine that can be exploited through malicious content submission. An attacker with content creation or editing permissions (but not necessarily direct CKEditor access) can craft payloads that execute JavaScript in the browser of users viewing or editing the content via CKEditor, including site administrators. A fix is available in Drupal 10.6.17, 11.3.17, and 11.4.7.

Affected products

Drupal Drupal 10.5.0–10.6.16, 11.0.0–11.3.16, 11.4.0–11.4.6
CKSource CKEditor 5 affected version range not specified in advisory

Timeline

2026-09-16: disclosed

References

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