Is CVE-2026-124491 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-124491 being exploited in the wild.

How severe is CVE-2026-124491?

Medium severity, with a CVSS score of 6.4, published 8 November 2026.

Is there a fix for CVE-2026-124491?

Yes: fixed in 3.4.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-124491 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-124491?

Check whether you run JiHong88 SunEditor at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-124491: SunEditor stored cross-site scripting in FileUpload plugin

CVE-2026-124491 · Severity: medium · CVSS 6.4 · Published 2026-11-08

SunEditor is a JavaScript rich text editor library used in web applications to allow users to create and edit formatted content. A flaw in its FileUpload plugin allows attackers to upload files with malicious names containing JavaScript code; when other users view the uploaded file in the editor or gallery, the injected code executes in their browser, potentially enabling session theft or unauthorized actions. The vulnerability persists across sessions as stored XSS.

Technologies: JiHong88 SunEditor. Vendors: JiHong88.

Quick answers

Is CVE-2026-124491 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-124491 being exploited in the wild.
How severe is CVE-2026-124491?: Medium severity, with a CVSS score of 6.4, published 8 November 2026.
Which products and versions are affected?: JiHong88 SunEditor < 3.4.0.
Is there a fix for CVE-2026-124491?: Yes: fixed in 3.4.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-124491 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-124491?: Check whether you run JiHong88 SunEditor at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: 3.4.0

Technical details

The FileUpload plugin's create() method passes the server-returned file.name field directly to the DOM via el.innerHTML = name in domUtils.js without HTML escaping. An attacker uploads a file with a name like "<img src=x onerror=alert(1)>.pdf"; the server echoes this name in the JSON response, which is then inserted into the editor content via component.insert() — bypassing the html.clean() sanitizer. The XSS fires immediately on upload and again when other users load the editor content or file gallery.

Affected products

JiHong88 SunEditor < 3.4.0

Timeline

2026-10-23: disclosed
2026-11-08: advisory

References

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