Winter CMS reflected XSS in backend Table widget search parameter

Quick answers

Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Medium severity, with a CVSS score of 4.5, published 20 August 2026.

Which products and versions are affected?

winter/wn-backend-module (Packagist) >= 1.0.420, <= 1.2.13.

Is there a fix for This vulnerability?

A patch was published on 2026-08-20: Fix released in v1.2.14 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network, in a web application.

Am I affected?

Check whether you run winter/wn-backend-module (Packagist) 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.

Technical details

This is a reflected cross-site scripting (XSS) vulnerability in the backend Table widget (`modules/backend/widgets/table/partials/_table.php`). The `search` query parameter is rendered without HTML encoding inside a `&lt;script type="text/template"&gt;` block. Because `&lt;script&gt;` is an HTML raw-text context, an attacker can include a literal `&lt;/script&gt;` terminator in the query string to break out of the template and inject arbitrary HTML/JavaScript. The vulnerable code reads from the global request via the `get()` helper, which is not restricted by HTTP method, allowing a simple GET request to trigger the vulnerability. Any backend page rendering a Table or DataTable widget is affected, including the Editor Settings form accessible to Developer-role users by default. A successful exploit requires inducing an authenticated backend user to visit an attacker-controlled link; the attacker can then read CSRF tokens and execute authenticated actions within the victim's permission scope. The patch applies HTML encoding via the `e()` function, matching handling elsewhere in the codebase.

Affected products

• Winter winter/wn-backend-module >= 1.0.420, <= 1.2.13

Timeline

• 2026-08-20: disclosed: GitHub Security Advisory published
• 2026-08-20: patched: Fix released in v1.2.14

References

• https://api.github.com/users/NRAwwad
• https://github.com/NRAwwad
• https://api.github.com/users/NRAwwad/gists%7B/gist_id%7D
• https://api.github.com/users/NRAwwad/repos
• https://avatars.githubusercontent.com/u/39842950?v=4
• https://api.github.com/users/NRAwwad/events%7B/privacy%7D