CVE-2024-45613

Cross-site scripting (XSS) in the clipboard package

Workarounds

It's highly recommended to update to the version 43.1.1 or higher. However, if the update is not an option, we recommend disabling the block toolbar plugin.

For more information

Email us at [email protected] if you have any questions or comments about this advisory.

During a recent internal audit, we identified a Cross-Site Scripting (XSS) vulnerability in the CKEditor 5 clipboard package. This vulnerability could be triggered by a specific user action, leading to unauthorized JavaScript code execution, if the attacker managed to insert a malicious content into the editor, which might happen with a very specific editor configuration.

This vulnerability affects only installations where the editor configuration meets the following criteria:

1. The Block Toolbar plugin is enabled.
2. One of the following plugins is also enabled:
   • General HTML Support with a configuration that permits unsafe markup.
   • HTML Embed.

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.

CVE-2024-45613 has a CVSS score of 7.2 (Medium). The vector is network-reachable, no privileges required, and no user interaction. 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 (43.1.1); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

The problem has been recognized and patched. The fix will be available in version 43.1.1 (and above), and explicitly in version 41.3.2.

1. What is CVE-2024-45613? CVE-2024-45613 is a medium-severity cross-site scripting (XSS) vulnerability in ckeditor5 (npm), affecting versions >= 40.0.0, < 43.1.1. It is fixed in 43.1.1. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2024-45613? CVE-2024-45613 has a CVSS score of 7.2 (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.
3. Which packages are affected by CVE-2024-45613?
   • ckeditor5 (npm) (versions >= 40.0.0, < 43.1.1)
   • @ckeditor/ckeditor5-clipboard (npm) (versions >= 40.0.0, < 43.1.1)
4. Is there a fix for CVE-2024-45613? Yes. CVE-2024-45613 is fixed in 43.1.1. Upgrade to this version or later.
5. Is CVE-2024-45613 exploitable, and should I be worried? Whether CVE-2024-45613 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
6. What actually determines whether CVE-2024-45613 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.
7. How do I fix CVE-2024-45613?
   • Upgrade ckeditor5 to 43.1.1 or later
   • Upgrade @ckeditor/ckeditor5-clipboard to 43.1.1 or later

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