CVE-2026-28343

Name: CVE-2026-28343
Creator: NVD / NIST
Published: 2026-03-05T20:16:16.017+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.27%

Last modified Jun 17, 2026

CVE-2026-28343 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. CKEditor 5 is a modern JavaScript rich-text editor with an MVC architecture. Starting in version 29.0.0 and prior to version 47.6.0, a cross-site scripting (XSS) vulnerability has been discovered in the General HTML Support feature. EPSS estimates a 0.27% chance of exploitation in the next 30 days.

Description

CKEditor 5 is a modern JavaScript rich-text editor with an MVC architecture. Starting in version 29.0.0 and prior to version 47.6.0, a cross-site scripting (XSS) vulnerability has been discovered in the General HTML Support feature. This vulnerability could be triggered by inserting specially crafted markup, leading to unauthorized JavaScript code execution, if the editor instance used an unsafe General HTML Support configuration. This issue has been patched in version 47.6.0.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

0.27%

18.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Ckeditor	Ckeditor5	< 47.6.0

References

https://github.com/ckeditor/ckeditor5/releases/tag/v29.0.0
https://github.com/ckeditor/ckeditor5/releases/tag/v47.6.0Release Notes
https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-jrqm-vmqc-gm93Mitigation, Vendor Advisory

Timeline

Published: Mar 5, 2026
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2026-28343?

How severe is CVE-2026-28343?

CVE-2026-28343 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2026-28343?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-28343?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST