CVE-2026-75170: HubCore Platform XSS Vulnerability

CVE-2026-75170 Overview

CVE-2026-75170 is a reflected cross-site scripting (XSS) vulnerability in the HubCore platform version 14.1.1. The flaw exists in the /loginController/doLogin endpoint, which fails to sanitize the language POST parameter before reflecting it into the application response. A remote, unauthenticated attacker can craft a malicious request that injects arbitrary JavaScript into the victim's browser session. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation).

Critical Impact
Successful exploitation allows attackers to execute arbitrary JavaScript in the context of an authenticated user's session, enabling credential theft, session hijacking, and phishing attacks against HubCore users.

Affected Products

HubCore platform version 14.1.1
Login controller component (/loginController/doLogin endpoint)
Deployments exposing the language POST parameter to unauthenticated users

Discovery Timeline

2026-09-04 - CVE-2026-75170 published to the National Vulnerability Database
2026-09-09 - Last updated in NVD database

Technical Details for CVE-2026-75170

Vulnerability Analysis

The vulnerability resides in the login handler exposed at /loginController/doLogin in HubCore 14.1.1. The endpoint accepts a language POST parameter and includes its value in the HTTP response without applying output encoding or input sanitization. An attacker who tricks a user into submitting a crafted request can cause the browser to execute injected JavaScript within the origin of the HubCore application.

Because the endpoint is reachable without authentication, exploitation does not require valid credentials. The reflected payload runs with the privileges of the victim's active session. This creates a viable pathway for session theft, credential harvesting through injected forms, and browser-based pivoting into internal HubCore functionality. Additional research artifacts are available in the GitHub CVE-2026-75170 research repository.

Root Cause

The root cause is missing output encoding on the language parameter before it is written to the HTTP response body. The application trusts client-supplied input and reflects it into HTML without contextual escaping. This is a textbook CWE-79 failure resulting from absent server-side validation and unsafe template rendering.

Attack Vector

Exploitation is network-based and requires user interaction, typically through a crafted link or a malicious form that auto-submits to the vulnerable endpoint. The attacker delivers the exploitation URL through phishing email, chat, or a compromised third-party site. When the victim's browser processes the response, the injected script executes in the HubCore origin. The scope-changed impact allows the attacker to access resources beyond the initially vulnerable component, including authenticated session data.

The vulnerability manifests when the language POST parameter contains HTML or JavaScript control characters. See the GitHub CVE-2026-75170 research repository for the proof-of-concept payload and reproduction steps.

Detection Methods for CVE-2026-75170

Indicators of Compromise

POST requests to /loginController/doLogin where the language parameter contains HTML tags, <script> fragments, javascript: URIs, or event handler attributes such as onerror or onload
URL-encoded payloads targeting the language field, including sequences like %3Cscript%3E or %3Cimg
Referrer headers pointing to attacker-controlled domains preceding requests to the login endpoint
Unexpected outbound requests from user browsers to external hosts immediately after visiting the HubCore login page

Detection Strategies

Deploy web application firewall (WAF) rules that inspect POST bodies to /loginController/doLogin for XSS payload patterns
Enable HTTP request logging on the HubCore reverse proxy and alert on suspicious characters in the language parameter
Correlate authentication events with anomalous JavaScript execution or session token access patterns in browser telemetry

Monitoring Recommendations

Baseline legitimate values of the language parameter and alert on deviations from the expected allowlist
Monitor for spikes in requests to the login endpoint originating from a small set of source IPs, indicating targeted phishing campaigns
Track user-reported phishing links referencing the HubCore domain and validate them against known exploitation patterns

How to Mitigate CVE-2026-75170

Immediate Actions Required

Restrict access to the HubCore login endpoint from untrusted networks where feasible until a patched version is deployed
Deploy WAF signatures that block XSS payloads submitted to the language POST parameter
Educate users to avoid clicking unsolicited links referencing the HubCore login URL
Rotate session cookies and enforce short session lifetimes to limit the value of stolen tokens

Patch Information

No vendor patch reference is listed in the NVD entry at the time of publication. Consult the Hubcore AI Platform vendor site for updated versions beyond 14.1.1 and apply security updates as they become available. Track the GitHub CVE-2026-75170 research repository for additional technical details.

Workarounds

Configure the reverse proxy to reject POST requests to /loginController/doLogin when the language parameter contains characters outside an approved allowlist such as [a-zA-Z_-]
Enforce a strict Content Security Policy (CSP) that disallows inline scripts and restricts script sources to trusted origins
Set the HttpOnly and Secure flags on session cookies to reduce impact from JavaScript-based token theft
Enable SameSite=Strict on authentication cookies to blunt cross-site delivery of exploitation requests

bash

# Example NGINX configuration to filter suspicious language parameter values
location /loginController/doLogin {
    if ($request_method = POST) {
        if ($request_body ~* "language=[^&]*(<|>|script|javascript:|onerror|onload)") {
            return 403;
        }
    }
    add_header Content-Security-Policy "default-src 'self'; script-src 'self'";
    add_header X-XSS-Protection "1; mode=block";
    proxy_pass http://hubcore_backend;
}