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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2021-21254 Detail

Description

CKEditor 5 is an open source rich text editor framework with a modular architecture. The CKEditor 5 Markdown plugin (@ckeditor/ckeditor5-markdown-gfm) before version 25.0.0 has a regex denial of service (ReDoS) vulnerability. The vulnerability allowed to abuse link recognition regular expression, which could cause a significant performance drop resulting in browser tab freeze. It affects all users using CKEditor 5 Markdown plugin at version <= 24.0.0. The problem has been recognized and patched. The fix will be available in version 25.0.0.


Severity

 


CVSS 3.x Severity and Metrics:

NIST CVSS score matches with CNA score
CNA:  GitHub, Inc.
Base Score:  6.5 MEDIUM
Vector:  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: The NVD and the CNA have provided the same score. When this occurs only the CNA information is displayed, but the Acceptance Level icon for the CNA is given a checkmark to signify NVD concurrence.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/ckeditor/ckeditor5/releases/tag/v25.0.0 Release Notes  Third Party Advisory 
https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-hgmg-hhc8-g5wr Third Party Advisory 
https://www.npmjs.com/package/@ckeditor/ckeditor5-markdown-gfm Release Notes  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-400 Uncontrolled Resource Consumption Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21254
NVD Published Date:
01/29/2021
NVD Last Modified:
08/09/2022
Source:
GitHub, Inc.