A regular expression denial of service (ReDoS) vulnerability has been discovered in multiple CKEditor 5 packages. The vulnerability allowed to abuse particular regular expressions, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 5 packages listed above at version <= 26.0.0.
The problem has been recognized and patched. The fix will be available in version 27.0.0.
Email us at [email protected] if you have any questions or comments about this advisory.
The CKEditor 5 team would like to thank Yeting Li for recognizing and reporting these vulnerabilities.
github.com/ckeditor/ckeditor5/releases/tag/v27.0.0
github.com/ckeditor/ckeditor5/security/advisories/GHSA-3rh3-wfr4-76mj
nvd.nist.gov/vuln/detail/CVE-2021-21391
www.npmjs.com/package/@ckeditor/ckeditor5-engine
www.npmjs.com/package/@ckeditor/ckeditor5-font
www.npmjs.com/package/@ckeditor/ckeditor5-image
www.npmjs.com/package/@ckeditor/ckeditor5-list
www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm
www.npmjs.com/package/@ckeditor/ckeditor5-media-embed
www.npmjs.com/package/@ckeditor/ckeditor5-paste-from-office
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