CVE-2026-116687: CKEditor: Cross-site scripting (XSS) in the engine package

Severity: low (CVSS 3.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-27 · updated 2026-10-28
Weakness: CWE-79

Description

CKEditor 5 is a modern JavaScript rich-text editor with an MVC architecture. From 29.0.0 until 47.7.4 and 48.5.1, specially crafted markup can trigger cross-site scripting when General HTML Support is enabled and specifically configured to allow object content. Processing that content can execute attacker-controlled JavaScript in a browser context isolated from the origin of the application embedding the editor. This issue is fixed in versions 47.7.4 and 48.5.1.

Affected products

ckeditor5: from 29.0.0, < 47.7.4; from 48.0.0, < 48.5.1

References

https://github.com/ckeditor/ckeditor5/commit/4d9c5bb34f63cd956d15ccafbe584e14280c86a0
https://github.com/ckeditor/ckeditor5/commit/a750e38635db6a18c5b11599c09f4fd702850423
https://github.com/ckeditor/ckeditor5/releases/tag/v47.7.4
https://github.com/ckeditor/ckeditor5/releases/tag/v48.5.1
https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-v6mg-96c6-gmpq

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