---
id: "CVE-2026-124494"
page: "https://infrastack.ai/live/CVE-2026-124494"
kind: "vulnerability"
aliases: ["CVE-2026-124494"]
title: "SunEditor: stored XSS via sanitizer entity decoding bypass"
severity: "critical"
cvss: 9.3
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "suneditor", "fixed": [], "affected": "", "ecosystem": "npm"}]
ecosystems: ["npm"]
tags: ["javascript", "package", "user-generated-content", "web-apps"]
not_affected_if: ["no-suneditor", "trusted-authors-only"]
published_at: "2026-11-08T14:18:19+00:00"
first_seen_at: "2026-11-08T14:48:42+00:00"
updated_at: "2026-11-08T14:50:52+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-124494", "first_seen_at": "2026-11-08T14:48:42+00:00"}]
exploit_sources: []
---

# SunEditor: stored XSS via sanitizer entity decoding bypass

Link for people: https://infrastack.ai/live/CVE-2026-124494 (this .md is for agents)

SunEditor, a rich-text editor library, has a flaw where its html.clean() sanitizer decodes named entities such as : to an empty string, letting attackers store javascript: links that pass the safety check. When a victim clicks a stored link, the attacker's JavaScript runs in their browser.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- npm:suneditor affected range not listed fixed no fixed version listed

## How to check

- Check the installed SunEditor version in the project's `package.json` or lockfile, looking for versions below `3.4.0`
- Search the codebase for `suneditor` to find where the editor and its `html.clean()` sanitizer are used

## Fix

- SunEditor: move to `3.4.0` or later

## Timeline

- 2026-11-08T14:48:42+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-124494

## Documents

- [advisory] Vendor advisory: github.com https://github.com/JiHong88/suneditor/security/advisories/GHSA-v4jx-8pj6-w4w8
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/suneditor-before-3.4.0-stored-xss-via-colon-entity-sanitizer-bypass

## From the sources

SunEditor before 3.4.0 contains a stored cross-site scripting vulnerability because the html.clean() sanitizer's _normalizeURL() function decodes named entities like : to an empty string. Attackers can inject href values such as javascript: that pass the _isSafeURL() check but are decoded by browsers, executing JavaScript when victims click stored links.

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