HighGHSA-6226-h7ff-ch6cCVE-2021-32808

Widget feature vulnerability allowing to execute JavaScript code using undo functionality

Published 23 Aug 2021 · Updated 8 Jul 2026

Affected package

Affected
>=4.13.0 <4.16.2
Fixed in
4.16.2
Update to the fixed version for your release line, for example:npm install ckeditor4@4.16.2

Details

Affected packages

The vulnerability has been discovered in Widget plugin if used alongside Undo feature.

Impact

A potential vulnerability has been discovered in CKEditor 4 Widget package. The vulnerability allowed to abuse undo functionality using malformed widget HTML, which could result in executing JavaScript code. It affects all users using the CKEditor 4 plugins listed above at version >= 4.13.0.

Patches

The problem has been recognized and patched. The fix will be available in version 4.16.2.

For more information

Email us at security@cksource.com if you have any questions or comments about this advisory.

Acknowledgements

The CKEditor 4 team would like to thank Anton Subbotin (skavans) for recognizing and reporting this vulnerability.

Is GHSA-6226-h7ff-ch6c in any of your client repos?

Checking one package by hand is fine. Checking it across forty client projects is not. NPMscan reads the lockfiles in every GitHub repo you pick, finds each project with an affected ckeditor4, and gives you the command that fixes it.

References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.