CKeditor5 up to 47.5.x General HTML Support Feature HTML injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability was found in CKeditor5 up to 47.5.x. It has been classified as problematic. The affected element is an unknown function of the component General HTML Support Feature. This manipulation causes HTML injection. This vulnerability appears as CVE-2026-28343. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in CKeditor5 up to 47.5.x. It has been declared as problematic. Affected by this vulnerability is an unknown code block of the component General HTML Support Feature. The manipulation with an unknown input leads to a html injection vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-28343 since 02/26/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 47.6.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

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Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔒

CNA Base Score: 6.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: HTML injection
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CKeditor5 47.6.0

Timelineinfo

02/26/2026 CVE reserved
03/06/2026 +8 days Advisory disclosed
03/06/2026 +0 days VulDB entry created
03/19/2026 +13 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-jrqm-vmqc-gm93
Status: Confirmed

CVE: CVE-2026-28343 (🔒)
GCVE (CVE): GCVE-0-2026-28343
GCVE (VulDB): GCVE-100-349333

Entryinfo

Created: 03/06/2026 07:23
Updated: 03/19/2026 23:07
Changes: 03/06/2026 07:23 (65), 03/10/2026 12:02 (1), 03/17/2026 20:06 (11), 03/19/2026 23:07 (1)
Complete: 🔍
Cache ID: 216::103

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