CVE-2026-124493
SunEditor before 3.4.0 Stored XSS via DocumentType Header textContent
Description
SunEditor before 3.4.0 contains a stored cross-site scripting vulnerability in the DocumentType constructor that injects header textContent into innerHTML without HTML escaping. Attackers can store entity-encoded HTML in h1-h6 headers that executes JavaScript when editors using document:header mode initialize, enabling session cookie theft.
INFO
Published Date :
Nov. 8, 2026, 1:16 p.m.
Last Modified :
Nov. 8, 2026, 1:16 p.m.
Remotely Exploit :
Yes !
Source :
VulnCheck
Affected Products
The following products are affected by CVE-2026-124493
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | CRITICAL | 83251b91-4cc7-4094-a5c7-464a1b83ea10 |
Solution
- Update SunEditor to version 3.4.0 or later.
- Ensure header content is properly escaped.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-124493 vulnerability anywhere in the article.