6.4

CVE-2026-28343: ckeditor ckeditor5 Cross-site Scripting

CVSS: 6.4v3.1MediumModified
AliasesUBUNTU-CVE-2026-28343GHSA-jrqm-vmqc-gm93
Published 05-03-2026Last modified 19-03-2026
Open JSON

Vulnerability summary

CVE-2026-28343 is a medium (CVSS 6.4) Cross-site Scripting vulnerability in ckeditor ckeditor5. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.3% of scored vulnerabilities.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.4/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.36%
0%100%
Low · +0.09 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 05-03-2026
    PublishedVulnerability first disclosed.
  2. 19-03-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

28%

Versus all other CVEs

30-day change

+0.09 pp

From 0.27% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.36%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu4 products
  • ckeditorAll versions (No fix recorded)
  • ckeditor3All versions (No fix recorded)
  • ldap-account-managerAll versions (No fix recorded)
  • request-tracker4All versions (No fix recorded)
@ckeditor1 product
  • ckeditor5-html-support≥ 29.0.0, < 47.6.0
Ckeditor1 product
Npm1 product
  • ckeditor5≥ 29.0.0, < 47.6.0

4 vendors · 7 products

References

7 links