CVE-2026-124493 json
SunEditor before 3.4.0 Stored XSS via DocumentType Header textContent
published 19d ago modified 3d ago also EUVD-2026-119548 , GHSA-h9pq-57qf-vvfh
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository JiHong88/suneditor. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 9.3
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- JiHong88 suneditor 3.4.0
Is CVE-2026-124493 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N |
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Inferred packages
No advisory lists a package for this vulnerability yet. The CVE names these as products and links their GitHub repository, and the package registry names the same repository, so they are probably the affected packages. Low confidence: the versions are the CVE’s own for the product, and a stack check reports the package as unchecked when there are none.
| ecosystem | package | repository | affected |
|---|---|---|---|
| npm | suneditor | jihong88/suneditor | < 3.4.0 |
Affected products
- JiHong88 suneditor
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/JiHong88/suneditor/security/advisories/GHSA-h9pq-57qf-vvfh
vendor-advisory, advisory
-
vulncheck.com
/advisories/suneditor-before-3.4.0-stored-xss-via-documenttype-header-textcontent
third-party-advisory
Sources
- CVE List CVE-2026-124493
- NVD CVE-2026-124493
- Maintainer advisory GHSA-h9pq-57qf-vvfh
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of JiHong88/suneditor published their own advisory on GitHub. Reviewed sources take precedence over it.