CVE-2026-46396
CVE-2026-46396 is a Cross-site Scripting (XSS) vulnerability in @haxtheweb/haxcms-nodejs. O3 Security confirms whether CVE-2026-46396 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Stored XSS via <iframe> in HAX CMS allows access to sensitive client-side data and account takeover
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-46396.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@haxtheweb/haxcms-nodejsnpm@haxtheweb/video-playernpm@haxtheweb/iframe-loadernpmDescription
Summary
A stored cross-site scripting (XSS) vulnerability exists in HAX CMS due to improper sanitization of <iframe> elements.
The application allows javascript: URIs in the src attribute, which are executed when a malicious page is viewed. This enables attackers to execute arbitrary JavaScript in the context of the victim’s browser and access sensitive data exposed to client-side scripts.
Details
Successful exploitation allows access to any data available in the browser context, including:
- Authentication tokens (e.g., JWT)
- Session cookies (if not protected with HttpOnly)
- Application configuration (e.g., window.appSettings)
- User-specific data accessible via APIs
This significantly increases the impact beyond simple script execution.
PoC
Steps to reproduce:
- Log in to HAX CMS as any authenticated user.
- Create a new page or edit an existing page.
- Open the HTML source editor (
<>). - Insert the following payload:
<iframe srcdoc="<script>
(function(){
try {
var jwt = parent.window.appSettings.jwt;
alert('Stolen JWT:\n' + jwt);
} catch(e) {
alert('Error: ' + e.message);
}
})();
</script>" style="display:none" sandbox="allow-scripts allow-same-origin"></iframe>
Impact
This vulnerability allows stored XSS leading to:
- Execution of arbitrary JavaScript in victim browsers
- Access to sensitive client-side data, including authentication tokens and session identifiers
- Unauthorized API actions performed on behalf of the victim
- Session hijacking and full account takeover
Because the application exposes authentication data in the client-side environment, exploitation of this vulnerability can lead to complete compromise of user accounts and site content.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @haxtheweb/haxcms-nodejs | all versions | 26.0.0 |
| 📦npm | @haxtheweb/video-player | all versions | 26.0.0 |
| 📦npm | @haxtheweb/iframe-loader | all versions | 26.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @haxtheweb/haxcms-nodejs. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @haxtheweb/haxcms-nodejs to 26.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-46396 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-46396 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-46396. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-46396 in your dependencies?
O3 detects CVE-2026-46396 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.