CVE-2026-46496

A stored cross-site scripting (XSS) vulnerability exists in HAX CMS due to improper sanitization of the <video-player> component.

The component allows javascript: URIs in the source attribute, which are executed when the page is viewed. This enables attackers to execute arbitrary JavaScript in the context of the victim’s browser and access sensitive data such as JWT tokens and more.

Details

The vulnerability is present in the <video-player> web component used within the HAX CMS editor.

The application fails to validate or sanitize user-supplied input in the following attributes:

• source
• source-data

These attributes accept arbitrary URI schemes, including javascript:, which leads to execution of attacker-controlled JavaScript in the browser.

Example vulnerable usage:

<video-player 
  source="javascript:alert(document.domain)" 
  source-type="external">
</video-player>

Because this content is stored and rendered to other users, the vulnerability is classified as a stored XSS.

The root cause is the lack of URI scheme validation and improper sanitization of component attributes before rendering.
Because this content is stored and rendered to other users, the vulnerability is classified as a stored XSS.

The root cause is the lack of URI scheme validation and improper sanitization of component attributes before rendering.

PoC

Steps to reproduce:

1. Log in to HAX CMS as user.
2. Create a website or any page and switch to the HTML source editor (<>).
3. Insert the following payload:

<video-player source="javascript:alert('JWT: '+localStorage.getItem('jwt').substring(0,30))" source-type="external"></video-player>

Save the page.

Reload or revisit or send the page.

Result

A JavaScript alert executes.
The JWT token is exposed.
This confirms arbitrary JavaScript execution in the victim’s browser.

This vulnerability allows stored XSS leading to:

• Theft of JWT authentication tokens
• Session hijacking
• Full account takeover
• Execution of arbitrary JavaScript in victim browsers

If an administrator views a malicious page, this can lead to full CMS compromise.

Attack complexity: Low
Privileges required: Low (any authenticated user)
User interaction: Required

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

Kodem intelligence

1. What is CVE-2026-46496? CVE-2026-46496 is a medium-severity cross-site scripting (XSS) vulnerability in @haxtheweb/haxcms-nodejs (npm), affecting versions <= 25.0.0. It is fixed in 26.0.0. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. Which packages are affected by CVE-2026-46496?
   • @haxtheweb/haxcms-nodejs (npm) (versions <= 25.0.0)
   • @haxtheweb/video-player (npm) (versions <= 25.0.0)
3. Is there a fix for CVE-2026-46496? Yes. CVE-2026-46496 is fixed in 26.0.0. Upgrade to this version or later.
4. Is CVE-2026-46496 exploitable, and should I be worried? Whether CVE-2026-46496 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2026-46496 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2026-46496?
   • Upgrade @haxtheweb/haxcms-nodejs to 26.0.0 or later
   • Upgrade @haxtheweb/video-player to 26.0.0 or later