CVE-2021-21391 Information

Description

CKEditor 5 provides a WYSIWYG editing solution. This CVE affects the following npm packages: ckeditor5-engine ckeditor5-font ckeditor5-image ckeditor5-list ckeditor5-markdown-gfm ckeditor5-media-embed ckeditor5-paste-from-office and ckeditor5-widget. Following an internal audit 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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Reference

https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm https://www.npmjs.com/package/@ckeditor/ckeditor5-engine https://www.npmjs.com/package/@ckeditor/ckeditor5-image https://www.npmjs.com/package/@ckeditor/ckeditor5-media-embed https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-3rh3-wfr4-76mj https://www.npmjs.com/package/@ckeditor/ckeditor5-list https://www.npmjs.com/package/@ckeditor/ckeditor5-font https://www.npmjs.com/package/@ckeditor/ckeditor5-paste-from-office https://www.npmjs.com/package/@ckeditor/ckeditor5-widget

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

REQUIRED

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

6.5