CVE-2026-28343: CKEditor 5 is a modern JavaScript rich-text editor with an MVC architecture

Q: How do I fix CVE-2026-28343?

ckeditor5: upgrade to 47.6.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-28343 being exploited?

CVE-2026-28343 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-28343 affect?

CVE-2026-28343 affects ckeditor5. Severity is medium (CVSS 6.4). 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 vu

Q: How urgent is CVE-2026-28343?

Priority 28/100. No elevated risk signals yet.

Routine

MEDIUM 6.4UPGRADE

CVE-2026-28343 is a medium-severity flaw (CVSS 6.4) affecting ckeditor5. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	6.4 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.3% (top 79%)
CISA exploited list	No
Weakness	CWE-79
Published	2026-03-05
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: ckeditor

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-03-05 20:16 UTCPublished CVE record published
2026-06-17 10:28 UTCUpdated Record last modified

ckeditor ckeditor5 UPGRADE

Affected: < 47.6.0

Fixed in: 47.6.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy ckeditor5 || rpm -q ckeditor5 || ckeditor5 --version

2. UPGRADE to 47.6.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade ckeditor5

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade ckeditor5

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-28343?

ckeditor5: upgrade to 47.6.0. Exact commands for each OS are on this page.

Is CVE-2026-28343 being exploited?

CVE-2026-28343 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-28343 affect?

CVE-2026-28343 affects ckeditor5. Severity is medium (CVSS 6.4). 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 vu

How urgent is CVE-2026-28343?

Priority 28/100. No elevated risk signals yet.

Related CVEs

CVE-2025-61261 MEDIUM 5.4 DOWNGRADE DOWNGRADE A reflected cross-site scripting (XSS) vulnerability in CKeditor v46.1.0 & Angular v18.0.0 allows attackers to
CVE-2024-45613 MEDIUM 6.1 UPGRADE CKEditor 5 is a JavaScript rich-text editor

References

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