CVE-2025-60956

Executive Summary

CVE-2025-60956 is a Cross-Site Request Forgery (CSRF) vulnerability identified in the EndRun Technologies Sonoma D12 Network Time Server (GPS) running firmware version 6010-0071-000 Ver 4.00. The vulnerability allows an attacker to trick an authenticated administrator into executing unintended actions, potentially leading to arbitrary code execution, denial of service, privilege escalation, and information disclosure. No public proof-of-concept (PoC) or patch is currently available. The EPSS score is 0.0%, indicating low exploitation likelihood at this time, but the impact is severe due to the device’s role in critical infrastructure time synchronization.

CVSS Breakdown & Threat Level

CVSS Score: 0.0 (No vector provided)
Severity: Unknown (likely High to Critical based on description)

Attack Vector (AV): Network (likely)
Attack Complexity (AC): Low (likely)
Privileges Required (PR): None (attacker does not need authentication)
User Interaction (UI): Required (victim must click a link or visit a malicious page)
Scope (S): Unchanged (likely)
Confidentiality (C): High (sensitive information disclosure)
Integrity (I): High (arbitrary code execution)
Availability (A): High (denial of service)

Threat Level: Critical – The device is a network time server used for precise time synchronization in industrial, financial, and government networks. A successful CSRF attack could disrupt operations, exfiltrate sensitive data, or provide persistent access.

Deep Dive & Mechanics

The Sonoma D12 NTP server provides a web-based management interface for configuration and monitoring. The CSRF vulnerability exists because the web application does not implement anti-CSRF tokens or origin validation in sensitive state-changing requests (e.g., firmware updates, user account creation, NTP configuration changes).

An attacker can craft a malicious HTML page that, when visited by an authenticated administrator, automatically submits a forged request to the NTP server’s web interface. Because the browser automatically includes the administrator’s session cookies, the server processes the request as legitimate.

Attack Flow:

1. Attacker identifies the target NTP server’s IP address (e.g., via Shodan).
2. Attacker crafts a malicious page containing a hidden form or JavaScript that sends a POST request to the server’s admin interface (e.g., to change NTP peers, add a new admin user, or trigger a firmware downgrade).
3. Attacker lures an authenticated administrator to visit the malicious page (e.g., via phishing email or compromised website).
4. The forged request executes with the administrator’s privileges, allowing the attacker to:
   • Execute arbitrary code (e.g., upload a malicious firmware image).
   • Cause denial of service (e.g., reset configuration to factory defaults).
   • Escalate privileges (e.g., create a new admin account).
   • Gain sensitive information (e.g., export logs or configuration files).

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):
The web application likely processes POST requests without verifying a CSRF token. Example vulnerable PHP/Node.js code:

// vulnerable.php
if ($_POST['action'] == 'update_firmware') {
    $file = $_FILES['firmware'];
    // No CSRF check
    upload_firmware($file);
}

Patched Code (Expected):
A patched version would include a CSRF token that is validated on every state-changing request:

// patched.php
session_start();
if ($_POST['action'] == 'update_firmware') {
    if (!hash_equals($_SESSION['csrf_token'], $_POST['csrf_token'])) {
        die('CSRF token mismatch');
    }
    $file = $_FILES['firmware'];
    upload_firmware($file);
}

Additionally, the server should validate the Origin or Referer header to ensure requests originate from the same domain.

Exploitation & Lab Setup

Red Team

Lab Environment:

• Target: EndRun Sonoma D12 with firmware 6010-0071-000 Ver 4.00 (or emulated via Docker/QEMU).
• Attacker: Kali Linux with a simple HTTP server.
• Victim: Browser with authenticated session to the NTP server.

Exploitation Steps:

1. Identify the target NTP server’s IP and admin interface endpoints (e.g., /admin/firmware, /admin/users).
2. Create a malicious HTML page that automatically submits a forged request:

<html>
<body>
<form id="csrf" action="http://<TARGET_IP>/admin/firmware" method="POST" enctype="multipart/form-data">
  <input type="hidden" name="action" value="upload">
  <input type="file" name="firmware" id="firmware">
</form>
<script>
  // Automatically submit the form with a malicious firmware file
  document.getElementById('csrf').submit();
</script>
</body>
</html>

3. Host the page on a local server: python3 -m http.server 8080.
4. Send the link to the victim (phishing email or social engineering).
5. Once the victim visits the page, the firmware upload request is sent with their session cookies.

Note: No public exploit code is available; this is a conceptual demonstration.

Blue Team

Detection & Prevention:

• Monitor for unusual POST requests to admin endpoints without a valid Referer header.
• Implement network segmentation to restrict access to the NTP server’s web interface to trusted admin IPs only.
• Use a web application firewall (WAF) to block requests missing CSRF tokens.
• Educate administrators about phishing attacks targeting network devices.

Indicators of Compromise (IOCs)

• Network IOCs:
  • Unusual POST requests to /admin/* endpoints from external IPs.
  • Requests with missing or spoofed Referer headers.
  • Multiple failed login attempts followed by successful CSRF-based actions.
• Host IOCs:
  • Unexpected firmware versions or configuration changes.
  • New user accounts created in the admin panel.
  • Log entries showing firmware uploads without corresponding user interaction.
• File IOCs:
  • Malicious firmware images with unexpected hashes (e.g., sha256sum mismatch).
  • Temporary files in /tmp or /var/tmp with suspicious names.

Detection Engineering

YARA Rule

rule CVE_2025_60956_CSRF_Exploit {
    meta:
        description = "Detects CSRF exploit attempts against EndRun Sonoma D12 NTP server"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-60956"
    strings:
        $csrf_form = /<form[^>]*action=["']http:\/\/[^"']*\/admin\// nocase
        $csrf_script = /document\.getElementById\(['"]csrf['"]\)\.submit\(\)/ nocase
        $firmware_upload = /enctype=["']multipart\/form-data["']/ nocase
    condition:
        any of them
}

Sigma Rule

title: CSRF Exploit Against EndRun Sonoma D12 NTP Server
id: 8a9b3c4d-5e6f-7a8b-9c0d-1e2f3a4b5c6d
status: experimental
description: Detects HTTP requests targeting admin endpoints without proper CSRF tokens
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
detection:
    selection:
        cs-method: 'POST'
        cs-uri-stem|startswith: '/admin/'
        cs-referer|contains: 'http://<TARGET_IP>/admin/'
    condition: selection
falsepositives:
    - Legitimate admin actions from trusted IPs
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"CVE-2025-60956 CSRF Exploit Against EndRun Sonoma D12";
    flow:to_server,established;
    content:"POST"; http_method;
    content:"/admin/"; http_uri;
    content:"Referer|3a|"; http_header;
    pcre:"/Referer\x3a\x20(?!http:\/\/<TARGET_IP>\/admin\/)/Pi";
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

Immediate Actions:

1. Isolate the device: Place the NTP server behind a firewall and restrict web interface access to trusted admin IPs only.
2. Disable unused services: If the web interface is not required, disable it via the device’s CLI or hardware switch.
3. Monitor logs: Enable detailed logging and review for suspicious POST requests.

Long-Term Fixes:

• Vendor Patch: Await an official firmware update from EndRun Technologies that implements CSRF tokens and origin validation.
• Workaround: Use a reverse proxy (e.g., Nginx) to add CSRF protection by validating the Origin header before forwarding requests to the NTP server.
• Network Segmentation: Place the NTP server in a dedicated management VLAN with strict access controls.

Valters IT Signature
This report was generated by Valters IT Cyber Threat Intelligence Division. For questions, contact cti@valters-it.com.