What is the CVSS score of CVE-2021-21391?

CVE-2021-21391 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H. EPSS exploitation probability: 1.7%.

Is there a patch available for CVE-2021-21391?

Yes, a patch is available for CVE-2021-21391. Update the affected software to the latest version immediately.

Node.js CVE-2021-21391

Q: Which versions of Node.js are affected by CVE-2021-21391?

CKEditor 5 provides a WYSIWYG editing solution. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.. A patch is available.

MEDIUM

Uncontrolled Resource Consumption (CWE-400)

2021-04-29 security-advisories@github.com

Denial Of Service Node.js Microsoft Ckeditor Ckeditor5 Engine Ckeditor5 Font Ckeditor5 Image Ckeditor5 List Ckeditor5 Markdown Gfm Ckeditor5 Media Embed Ckeditor5 Paste From Office Ckeditor5 Widget

6.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.5 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

CVE Published

Apr 29, 2021 - 01:15 nvd

MEDIUM 6.5

DescriptionNVD

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.

AnalysisAI

CKEditor 5 provides a WYSIWYG editing solution. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. 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. Affected products include: Ckeditor Ckeditor5-Engine, Ckeditor Ckeditor5-Font, Ckeditor Ckeditor5-Image, Ckeditor Ckeditor5-List, Ckeditor Ckeditor5-Markdown-Gfm. Version information: version 27.0.0..

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.